---
_id: '63997'
abstract:
- lang: eng
text: Abstract Herein we report the mechanochemical Friedel-Crafts alkylation of
1,3,5-triphenylbenzene (TPB) with two organochloride cross-linking agents, dichloromethane
(DCM) and chloroform (CHCl3), respectively. During a thorough milling parameter
evaluation, the DCM-linked polymers were found to be flexible and extremely sensitive
toward parameter changes, which even enables the synthesis of a polymer with a
SSABET of 1670 m2/g, on par with the solution-based reference. Contrary, CHCl3-linked
polymers are exhibiting a rigid structure, with a high porosity that is widely
unaffected by parameter changes. As a result, a polymer with a SSABET of 1280
m2/g could be generated in as little as 30 minutes, outperforming the reported
literature analogue in terms of synthesis time and SSABET. To underline the environmental
benefits of our fast and solvent-free synthesis approach, the green metrics are
discussed, revealing an enhancement of the mass intensity, mass productivity and
the E-factor, as well as of synthesis time and the work-up in comparison to the
classical synthesis. Therefore, the mechanochemical polymerization is presented
as a versatile tool, enabling the generation of highly porous polymers within
short reaction times, with a minimal use of chlorinated cross-linker and with
the possibility of a post polymerization modification.
author:
- first_name: Annika
full_name: Krusenbaum, Annika
last_name: Krusenbaum
- first_name: Jonathan
full_name: Geisler, Jonathan
last_name: Geisler
- first_name: Fabien Joel Leon
full_name: Kraus, Fabien Joel Leon
last_name: Kraus
- first_name: Sven
full_name: Grätz, Sven
last_name: Grätz
- first_name: Mark Valentin
full_name: Höfler, Mark Valentin
last_name: Höfler
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Lars
full_name: Borchardt, Lars
last_name: Borchardt
citation:
ama: Krusenbaum A, Geisler J, Kraus FJL, et al. The mechanochemical Friedel-Crafts
polymerization as a solvent-free cross-linking approach toward microporous polymers.
Journal of Polymer Science. 2022;60(1):62–71. doi:10.1002/pol.20210606
apa: Krusenbaum, A., Geisler, J., Kraus, F. J. L., Grätz, S., Höfler, M. V., Gutmann,
T., & Borchardt, L. (2022). The mechanochemical Friedel-Crafts polymerization
as a solvent-free cross-linking approach toward microporous polymers. Journal
of Polymer Science, 60(1), 62–71. https://doi.org/10.1002/pol.20210606
bibtex: '@article{Krusenbaum_Geisler_Kraus_Grätz_Höfler_Gutmann_Borchardt_2022,
title={The mechanochemical Friedel-Crafts polymerization as a solvent-free cross-linking
approach toward microporous polymers}, volume={60}, DOI={10.1002/pol.20210606},
number={1}, journal={Journal of Polymer Science}, author={Krusenbaum, Annika and
Geisler, Jonathan and Kraus, Fabien Joel Leon and Grätz, Sven and Höfler, Mark
Valentin and Gutmann, Torsten and Borchardt, Lars}, year={2022}, pages={62–71}
}'
chicago: 'Krusenbaum, Annika, Jonathan Geisler, Fabien Joel Leon Kraus, Sven Grätz,
Mark Valentin Höfler, Torsten Gutmann, and Lars Borchardt. “The Mechanochemical
Friedel-Crafts Polymerization as a Solvent-Free Cross-Linking Approach toward
Microporous Polymers.” Journal of Polymer Science 60, no. 1 (2022): 62–71.
https://doi.org/10.1002/pol.20210606.'
ieee: 'A. Krusenbaum et al., “The mechanochemical Friedel-Crafts polymerization
as a solvent-free cross-linking approach toward microporous polymers,” Journal
of Polymer Science, vol. 60, no. 1, pp. 62–71, 2022, doi: 10.1002/pol.20210606.'
mla: Krusenbaum, Annika, et al. “The Mechanochemical Friedel-Crafts Polymerization
as a Solvent-Free Cross-Linking Approach toward Microporous Polymers.” Journal
of Polymer Science, vol. 60, no. 1, 2022, pp. 62–71, doi:10.1002/pol.20210606.
short: A. Krusenbaum, J. Geisler, F.J.L. Kraus, S. Grätz, M.V. Höfler, T. Gutmann,
L. Borchardt, Journal of Polymer Science 60 (2022) 62–71.
date_created: 2026-02-07T15:50:44Z
date_updated: 2026-02-17T16:16:01Z
doi: 10.1002/pol.20210606
extern: '1'
intvolume: ' 60'
issue: '1'
language:
- iso: eng
page: 62–71
publication: Journal of Polymer Science
status: public
title: The mechanochemical Friedel-Crafts polymerization as a solvent-free cross-linking
approach toward microporous polymers
type: journal_article
user_id: '100715'
volume: 60
year: '2022'
...
---
_id: '63983'
abstract:
- lang: eng
text: Polyethylene glycol (PEG) is increasingly used as an alternative green chemical
solvent. New experimental measurements on density, viscosity, and self-diffusion
coefficient are presented for PEG200, PEG400, and several binary mixtures of tri-
and hexaethylene glycol covering a temperature range from 298.15 to 358.15 K.
Because PEGs are polydisperse, the exact compositions of PEG200 from six different
vendors are analytically determined and found to be comparable. Thus, only two
of the most differing PEG200 samples are further examined. The effects of water
as the most common impurity on densities, viscosities, and self-diffusion coefficients
are inspected as well as the results of the “dry” samples obtained by extrapolation
to zero water content. The obtained results are carefully compared to the available
literature data. The temperature dependence of these physical properties is investigated
and found to be linear for density, while viscosity and self-diffusion coefficients
follow the Arrhenius law. Attempts to calculate the properties of the binary mixtures
and PEG200 samples from the mole fraction weighted average of the physical properties
of the mixture components result in reasonable agreement. Agreement between calculated
and measured molar volumes is within measurement uncertainty. Agreement of calculated
and measured viscosities is mostly within a few percent but increases with decreasing
temperature (largest viscosities) reaching values of up to 15%. Similarly, calculated
and measured self-diffusion coefficients mostly agree within 20%, which is near
the measurement uncertainty, but overestimates increase to 30% for the highest
temperatures (largest self-diffusion coefficients).
author:
- first_name: Markus M.
full_name: Hoffmann, Markus M.
last_name: Hoffmann
- first_name: Joseph D.
full_name: Kealy, Joseph D.
last_name: Kealy
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
citation:
ama: Hoffmann MM, Kealy JD, Gutmann T, Buntkowsky G. Densities, Viscosities, and
Self-Diffusion Coefficients of Several Polyethylene Glycols. Journal of Chemical
and Engineering Data. 2022;67(1):88–103. doi:10.1021/acs.jced.1c00759
apa: Hoffmann, M. M., Kealy, J. D., Gutmann, T., & Buntkowsky, G. (2022). Densities,
Viscosities, and Self-Diffusion Coefficients of Several Polyethylene Glycols.
Journal of Chemical and Engineering Data, 67(1), 88–103. https://doi.org/10.1021/acs.jced.1c00759
bibtex: '@article{Hoffmann_Kealy_Gutmann_Buntkowsky_2022, title={Densities, Viscosities,
and Self-Diffusion Coefficients of Several Polyethylene Glycols}, volume={67},
DOI={10.1021/acs.jced.1c00759},
number={1}, journal={Journal of Chemical and Engineering Data}, publisher={American
Chemical Society}, author={Hoffmann, Markus M. and Kealy, Joseph D. and Gutmann,
Torsten and Buntkowsky, Gerd}, year={2022}, pages={88–103} }'
chicago: 'Hoffmann, Markus M., Joseph D. Kealy, Torsten Gutmann, and Gerd Buntkowsky.
“Densities, Viscosities, and Self-Diffusion Coefficients of Several Polyethylene
Glycols.” Journal of Chemical and Engineering Data 67, no. 1 (2022): 88–103.
https://doi.org/10.1021/acs.jced.1c00759.'
ieee: 'M. M. Hoffmann, J. D. Kealy, T. Gutmann, and G. Buntkowsky, “Densities, Viscosities,
and Self-Diffusion Coefficients of Several Polyethylene Glycols,” Journal of
Chemical and Engineering Data, vol. 67, no. 1, pp. 88–103, 2022, doi: 10.1021/acs.jced.1c00759.'
mla: Hoffmann, Markus M., et al. “Densities, Viscosities, and Self-Diffusion Coefficients
of Several Polyethylene Glycols.” Journal of Chemical and Engineering Data,
vol. 67, no. 1, American Chemical Society, 2022, pp. 88–103, doi:10.1021/acs.jced.1c00759.
short: M.M. Hoffmann, J.D. Kealy, T. Gutmann, G. Buntkowsky, Journal of Chemical
and Engineering Data 67 (2022) 88–103.
date_created: 2026-02-07T15:44:52Z
date_updated: 2026-02-17T16:16:54Z
doi: 10.1021/acs.jced.1c00759
extern: '1'
intvolume: ' 67'
issue: '1'
language:
- iso: eng
page: 88–103
publication: Journal of Chemical and Engineering Data
publisher: American Chemical Society
status: public
title: Densities, Viscosities, and Self-Diffusion Coefficients of Several Polyethylene
Glycols
type: journal_article
user_id: '100715'
volume: 67
year: '2022'
...
---
_id: '63948'
abstract:
- lang: eng
text: In this work, the behavior of four different commercially available polarizing
agents is investigated employing the non-ionic model surfactant 1-octanol as analyte.
A relative method for the comparison of the proportion of the direct and indirect
polarization transfer pathways is established, allowing a direct comparison of
the polarization efficacy for different radicals and different parts of the 1-octanol
molecule despite differences in radical concentration or sample amount. With this
approach, it could be demonstrated that the hydrophilicity is a key factor in
the way polarization is transferred from the polarizing agent to the analyte.
These findings are confirmed by the determination of buildup times Tb, illustrating
that the choice of polarizing agent plays an essential role in ensuring an optimal
polarization transfer and therefore the maximum amount of enhancement possible
for DNP enhanced NMR measurements.
author:
- first_name: Sonja C.
full_name: Döller, Sonja C.
last_name: Döller
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Markus
full_name: Hoffmann, Markus
last_name: Hoffmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
citation:
ama: Döller SC, Gutmann T, Hoffmann M, Buntkowsky G. A case study on the influence
of hydrophilicity on the signal enhancement by dynamic nuclear polarization. Solid
State Nuclear Magnetic Resonance. 2022;122:101829.
apa: Döller, S. C., Gutmann, T., Hoffmann, M., & Buntkowsky, G. (2022). A case
study on the influence of hydrophilicity on the signal enhancement by dynamic
nuclear polarization. Solid State Nuclear Magnetic Resonance, 122,
101829.
bibtex: '@article{Döller_Gutmann_Hoffmann_Buntkowsky_2022, title={A case study on
the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization},
volume={122}, journal={Solid State Nuclear Magnetic Resonance}, author={Döller,
Sonja C. and Gutmann, Torsten and Hoffmann, Markus and Buntkowsky, Gerd}, year={2022},
pages={101829} }'
chicago: 'Döller, Sonja C., Torsten Gutmann, Markus Hoffmann, and Gerd Buntkowsky.
“A Case Study on the Influence of Hydrophilicity on the Signal Enhancement by
Dynamic Nuclear Polarization.” Solid State Nuclear Magnetic Resonance 122
(2022): 101829.'
ieee: S. C. Döller, T. Gutmann, M. Hoffmann, and G. Buntkowsky, “A case study on
the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization,”
Solid State Nuclear Magnetic Resonance, vol. 122, p. 101829, 2022.
mla: Döller, Sonja C., et al. “A Case Study on the Influence of Hydrophilicity on
the Signal Enhancement by Dynamic Nuclear Polarization.” Solid State Nuclear
Magnetic Resonance, vol. 122, 2022, p. 101829.
short: S.C. Döller, T. Gutmann, M. Hoffmann, G. Buntkowsky, Solid State Nuclear
Magnetic Resonance 122 (2022) 101829.
date_created: 2026-02-07T09:13:08Z
date_updated: 2026-02-17T16:18:26Z
extern: '1'
intvolume: ' 122'
keyword:
- DNP NMR
- Dynamics
- Low temperature NMR
- Octanol
- Solid state NMR
- Surfactants
language:
- iso: eng
page: '101829'
publication: Solid State Nuclear Magnetic Resonance
status: public
title: A case study on the influence of hydrophilicity on the signal enhancement by
dynamic nuclear polarization
type: journal_article
user_id: '100715'
volume: 122
year: '2022'
...
---
_id: '63944'
abstract:
- lang: eng
text: Abstract The donor properties of a set of bulky ferrocene based bisphosphanes
(Fe(C5H4PMes2)2 and (C5H4PMes2)Fe(C5H4PtBu2 with Mes= mesityl and tBu=tert-butyl)
were probed by exploring the NMR parameters of the corresponding selenophosphoranes
amended by cyclovoltammetry. The ligand properties were explored in the complexation
of copper phenylacetylide which is relevant as intermediate in the Cu(I) catalyzed
CO2 addition to phenylacetylene. Owing to the poor solubility of the resulting
complexes their characterization was performed with solid state NMR spectroscopy
amended by IR spectroscopy, mass spectrometry and elemental analysis. Remarkably,
these complexes feature luminescent properties, albeit with limited quantum yield.
author:
- first_name: Subhayan
full_name: Dey, Subhayan
last_name: Dey
- first_name: Fabian
full_name: Roesler, Fabian
last_name: Roesler
- first_name: Mark V.
full_name: Höfler, Mark V.
last_name: Höfler
- first_name: Clemens
full_name: Bruhn, Clemens
last_name: Bruhn
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Rudolf
full_name: Pietschnig, Rudolf
last_name: Pietschnig
citation:
ama: Dey S, Roesler F, Höfler MV, Bruhn C, Gutmann T, Pietschnig R. Synthesis, Structure
and Cu-Phenylacetylide Coordination of an Unsymmetrically Substituted Bulky dppf-Analog.
European Journal of Inorganic Chemistry. 2022;2022(3):e202100939. doi:10.1002/ejic.202100939
apa: Dey, S., Roesler, F., Höfler, M. V., Bruhn, C., Gutmann, T., & Pietschnig,
R. (2022). Synthesis, Structure and Cu-Phenylacetylide Coordination of an Unsymmetrically
Substituted Bulky dppf-Analog. European Journal of Inorganic Chemistry,
2022(3), e202100939. https://doi.org/10.1002/ejic.202100939
bibtex: '@article{Dey_Roesler_Höfler_Bruhn_Gutmann_Pietschnig_2022, title={Synthesis,
Structure and Cu-Phenylacetylide Coordination of an Unsymmetrically Substituted
Bulky dppf-Analog}, volume={2022}, DOI={10.1002/ejic.202100939},
number={3}, journal={European Journal of Inorganic Chemistry}, author={Dey, Subhayan
and Roesler, Fabian and Höfler, Mark V. and Bruhn, Clemens and Gutmann, Torsten
and Pietschnig, Rudolf}, year={2022}, pages={e202100939} }'
chicago: 'Dey, Subhayan, Fabian Roesler, Mark V. Höfler, Clemens Bruhn, Torsten
Gutmann, and Rudolf Pietschnig. “Synthesis, Structure and Cu-Phenylacetylide Coordination
of an Unsymmetrically Substituted Bulky Dppf-Analog.” European Journal of Inorganic
Chemistry 2022, no. 3 (2022): e202100939. https://doi.org/10.1002/ejic.202100939.'
ieee: 'S. Dey, F. Roesler, M. V. Höfler, C. Bruhn, T. Gutmann, and R. Pietschnig,
“Synthesis, Structure and Cu-Phenylacetylide Coordination of an Unsymmetrically
Substituted Bulky dppf-Analog,” European Journal of Inorganic Chemistry,
vol. 2022, no. 3, p. e202100939, 2022, doi: 10.1002/ejic.202100939.'
mla: Dey, Subhayan, et al. “Synthesis, Structure and Cu-Phenylacetylide Coordination
of an Unsymmetrically Substituted Bulky Dppf-Analog.” European Journal of Inorganic
Chemistry, vol. 2022, no. 3, 2022, p. e202100939, doi:10.1002/ejic.202100939.
short: S. Dey, F. Roesler, M.V. Höfler, C. Bruhn, T. Gutmann, R. Pietschnig, European
Journal of Inorganic Chemistry 2022 (2022) e202100939.
date_created: 2026-02-07T09:11:00Z
date_updated: 2026-02-17T16:18:34Z
doi: 10.1002/ejic.202100939
extern: '1'
intvolume: ' 2022'
issue: '3'
language:
- iso: eng
page: e202100939
publication: European Journal of Inorganic Chemistry
status: public
title: Synthesis, Structure and Cu-Phenylacetylide Coordination of an Unsymmetrically
Substituted Bulky dppf-Analog
type: journal_article
user_id: '100715'
volume: 2022
year: '2022'
...
---
_id: '63943'
abstract:
- lang: eng
text: A lithium halide exchange reaction at low-temperature, via the treatment of
2,6-di(isopropyl)phenyllithium on 1,1′-bis-(dichlorophosphino)ferrocene, resulted
in the first isolated example of an aryl-substituted diphospha [2]ferrocenophane
(diphospha [2]FCP) 2. Although compound 2 did not show any recognizable thermal
reaction at higher temperature (up to 350 °C), its tert-butyl-substituted counterpart
1 underwent a clean selective heat-mediated P–C cleavage reaction, followed
by an inter-molecular rearrangement, to produce a P–P fused bis [3]ferrocenophane
3 with all-trans oriented P-chain, which upon further heating gave a polyferrocenylphosphane
tBu-[Fc’P2]n-tBu (4). Since polymer 4 is insoluble in common organic solvents,
it has been characterized with solid-state techniques, including solid-state NMR.
Density functional theory (DFT) has further been employed to identify possible
pathways for P–C bond cleavage on 1 and 2, as well as to evaluate accessible
pathways for further polymerization toward 4.
author:
- first_name: Subhayan
full_name: Dey, Subhayan
last_name: Dey
- first_name: Denis
full_name: Kargin, Denis
last_name: Kargin
- first_name: Mark V.
full_name: Höfler, Mark V.
last_name: Höfler
- first_name: Balazs
full_name: Szathmari, Balazs
last_name: Szathmari
- first_name: Clemens
full_name: Bruhn, Clemens
last_name: Bruhn
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Zsolt
full_name: Kelemen, Zsolt
last_name: Kelemen
- first_name: Rudolf
full_name: Pietschnig, Rudolf
last_name: Pietschnig
citation:
ama: Dey S, Kargin D, Höfler MV, et al. Oligo- and polymerization of phospha [2]ferrocenophanes
to one dimensional phosphorus chains with ferrocenylene handles. Polymer.
2022;242:124589.
apa: Dey, S., Kargin, D., Höfler, M. V., Szathmari, B., Bruhn, C., Gutmann, T.,
Kelemen, Z., & Pietschnig, R. (2022). Oligo- and polymerization of phospha
[2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles.
Polymer, 242, 124589.
bibtex: '@article{Dey_Kargin_Höfler_Szathmari_Bruhn_Gutmann_Kelemen_Pietschnig_2022,
title={Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional
phosphorus chains with ferrocenylene handles}, volume={242}, journal={Polymer},
author={Dey, Subhayan and Kargin, Denis and Höfler, Mark V. and Szathmari, Balazs
and Bruhn, Clemens and Gutmann, Torsten and Kelemen, Zsolt and Pietschnig, Rudolf},
year={2022}, pages={124589} }'
chicago: 'Dey, Subhayan, Denis Kargin, Mark V. Höfler, Balazs Szathmari, Clemens
Bruhn, Torsten Gutmann, Zsolt Kelemen, and Rudolf Pietschnig. “Oligo- and Polymerization
of Phospha [2]Ferrocenophanes to One Dimensional Phosphorus Chains with Ferrocenylene
Handles.” Polymer 242 (2022): 124589.'
ieee: S. Dey et al., “Oligo- and polymerization of phospha [2]ferrocenophanes
to one dimensional phosphorus chains with ferrocenylene handles,” Polymer,
vol. 242, p. 124589, 2022.
mla: Dey, Subhayan, et al. “Oligo- and Polymerization of Phospha [2]Ferrocenophanes
to One Dimensional Phosphorus Chains with Ferrocenylene Handles.” Polymer,
vol. 242, 2022, p. 124589.
short: S. Dey, D. Kargin, M.V. Höfler, B. Szathmari, C. Bruhn, T. Gutmann, Z. Kelemen,
R. Pietschnig, Polymer 242 (2022) 124589.
date_created: 2026-02-07T09:10:38Z
date_updated: 2026-02-17T16:18:36Z
extern: '1'
intvolume: ' 242'
keyword:
- solid-state nmr
- Ansa-ferrocene
- DFT calculations
- Oligophosphine
- Polyphosphane
- Ring-opening polymerization
language:
- iso: eng
page: '124589'
publication: Polymer
status: public
title: Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional
phosphorus chains with ferrocenylene handles
type: journal_article
user_id: '100715'
volume: 242
year: '2022'
...
---
_id: '63934'
author:
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Sonja
full_name: Döller, Sonja
last_name: Döller
- first_name: Nadia
full_name: Haro-Mares, Nadia
last_name: Haro-Mares
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Markus
full_name: Hoffmann, Markus
last_name: Hoffmann
citation:
ama: Buntkowsky G, Döller S, Haro-Mares N, Gutmann T, Hoffmann M. Solid-state NMR
studies of non-ionic surfactants confined in mesoporous silica. Zeitschrift
für Physikalische Chemie. 2022;236(6-8):939–960. doi:10.1515/zpch-2021-3132
apa: Buntkowsky, G., Döller, S., Haro-Mares, N., Gutmann, T., & Hoffmann, M.
(2022). Solid-state NMR studies of non-ionic surfactants confined in mesoporous
silica. Zeitschrift Für Physikalische Chemie, 236(6–8), 939–960.
https://doi.org/10.1515/zpch-2021-3132
bibtex: '@article{Buntkowsky_Döller_Haro-Mares_Gutmann_Hoffmann_2022, title={Solid-state
NMR studies of non-ionic surfactants confined in mesoporous silica}, volume={236},
DOI={10.1515/zpch-2021-3132},
number={6–8}, journal={Zeitschrift für Physikalische Chemie}, author={Buntkowsky,
Gerd and Döller, Sonja and Haro-Mares, Nadia and Gutmann, Torsten and Hoffmann,
Markus}, year={2022}, pages={939–960} }'
chicago: 'Buntkowsky, Gerd, Sonja Döller, Nadia Haro-Mares, Torsten Gutmann, and
Markus Hoffmann. “Solid-State NMR Studies of Non-Ionic Surfactants Confined in
Mesoporous Silica.” Zeitschrift Für Physikalische Chemie 236, no. 6–8 (2022):
939–960. https://doi.org/10.1515/zpch-2021-3132.'
ieee: 'G. Buntkowsky, S. Döller, N. Haro-Mares, T. Gutmann, and M. Hoffmann, “Solid-state
NMR studies of non-ionic surfactants confined in mesoporous silica,” Zeitschrift
für Physikalische Chemie, vol. 236, no. 6–8, pp. 939–960, 2022, doi: 10.1515/zpch-2021-3132.'
mla: Buntkowsky, Gerd, et al. “Solid-State NMR Studies of Non-Ionic Surfactants
Confined in Mesoporous Silica.” Zeitschrift Für Physikalische Chemie, vol.
236, no. 6–8, 2022, pp. 939–960, doi:10.1515/zpch-2021-3132.
short: G. Buntkowsky, S. Döller, N. Haro-Mares, T. Gutmann, M. Hoffmann, Zeitschrift
Für Physikalische Chemie 236 (2022) 939–960.
date_created: 2026-02-07T09:04:06Z
date_updated: 2026-02-17T16:18:55Z
doi: 10.1515/zpch-2021-3132
extern: '1'
intvolume: ' 236'
issue: 6-8
language:
- iso: eng
page: 939–960
publication: Zeitschrift für Physikalische Chemie
status: public
title: Solid-state NMR studies of non-ionic surfactants confined in mesoporous silica
type: journal_article
user_id: '100715'
volume: 236
year: '2022'
...
---
_id: '63932'
author:
- first_name: G.
full_name: Buntkowsky, G.
last_name: Buntkowsky
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
citation:
ama: Buntkowsky G, Gutmann T. PASADENA NMR. Nature Catalysis. 2022;5:848–849.
apa: Buntkowsky, G., & Gutmann, T. (2022). PASADENA NMR. Nature Catalysis,
5, 848–849.
bibtex: '@article{Buntkowsky_Gutmann_2022, title={PASADENA NMR}, volume={5}, journal={Nature
Catalysis}, author={Buntkowsky, G. and Gutmann, Torsten}, year={2022}, pages={848–849}
}'
chicago: 'Buntkowsky, G., and Torsten Gutmann. “PASADENA NMR.” Nature Catalysis
5 (2022): 848–849.'
ieee: G. Buntkowsky and T. Gutmann, “PASADENA NMR,” Nature Catalysis, vol.
5, pp. 848–849, 2022.
mla: Buntkowsky, G., and Torsten Gutmann. “PASADENA NMR.” Nature Catalysis,
vol. 5, 2022, pp. 848–849.
short: G. Buntkowsky, T. Gutmann, Nature Catalysis 5 (2022) 848–849.
date_created: 2026-02-07T09:02:44Z
date_updated: 2026-02-17T16:18:59Z
extern: '1'
intvolume: ' 5'
language:
- iso: eng
page: 848–849
publication: Nature Catalysis
status: public
title: PASADENA NMR
type: journal_article
user_id: '100715'
volume: 5
year: '2022'
...
---
_id: '63923'
author:
- first_name: Nargiz B.
full_name: Asanbaeva, Nargiz B.
last_name: Asanbaeva
- first_name: Larisa Yu
full_name: Gurskaya, Larisa Yu
last_name: Gurskaya
- first_name: Yuliya F.
full_name: Polienko, Yuliya F.
last_name: Polienko
- first_name: Tatyana V.
full_name: Rybalova, Tatyana V.
last_name: Rybalova
- first_name: Maxim S.
full_name: Kazantsev, Maxim S.
last_name: Kazantsev
- first_name: Alexey A.
full_name: Dmitriev, Alexey A.
last_name: Dmitriev
- first_name: Nina P.
full_name: Gritsan, Nina P.
last_name: Gritsan
- first_name: Nadia
full_name: Haro-Mares, Nadia
last_name: Haro-Mares
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Evgeny V.
full_name: Tretyakov, Evgeny V.
last_name: Tretyakov
- first_name: Elena G.
full_name: Bagryanskaya, Elena G.
last_name: Bagryanskaya
citation:
ama: Asanbaeva NB, Gurskaya LY, Polienko YF, et al. Effects of Spiro-Cyclohexane
Substitution of Nitroxyl Biradicals on Dynamic Nuclear Polarization. Molecules.
2022;27(10):3252. doi:10.3390/molecules27103252
apa: Asanbaeva, N. B., Gurskaya, L. Y., Polienko, Y. F., Rybalova, T. V., Kazantsev,
M. S., Dmitriev, A. A., Gritsan, N. P., Haro-Mares, N., Gutmann, T., Buntkowsky,
G., Tretyakov, E. V., & Bagryanskaya, E. G. (2022). Effects of Spiro-Cyclohexane
Substitution of Nitroxyl Biradicals on Dynamic Nuclear Polarization. Molecules,
27(10), 3252. https://doi.org/10.3390/molecules27103252
bibtex: '@article{Asanbaeva_Gurskaya_Polienko_Rybalova_Kazantsev_Dmitriev_Gritsan_Haro-Mares_Gutmann_Buntkowsky_et
al._2022, title={Effects of Spiro-Cyclohexane Substitution of Nitroxyl Biradicals
on Dynamic Nuclear Polarization}, volume={27}, DOI={10.3390/molecules27103252},
number={10}, journal={Molecules}, author={Asanbaeva, Nargiz B. and Gurskaya, Larisa
Yu and Polienko, Yuliya F. and Rybalova, Tatyana V. and Kazantsev, Maxim S. and
Dmitriev, Alexey A. and Gritsan, Nina P. and Haro-Mares, Nadia and Gutmann, Torsten
and Buntkowsky, Gerd and et al.}, year={2022}, pages={3252} }'
chicago: 'Asanbaeva, Nargiz B., Larisa Yu Gurskaya, Yuliya F. Polienko, Tatyana
V. Rybalova, Maxim S. Kazantsev, Alexey A. Dmitriev, Nina P. Gritsan, et al. “Effects
of Spiro-Cyclohexane Substitution of Nitroxyl Biradicals on Dynamic Nuclear Polarization.”
Molecules 27, no. 10 (2022): 3252. https://doi.org/10.3390/molecules27103252.'
ieee: 'N. B. Asanbaeva et al., “Effects of Spiro-Cyclohexane Substitution
of Nitroxyl Biradicals on Dynamic Nuclear Polarization,” Molecules, vol.
27, no. 10, p. 3252, 2022, doi: 10.3390/molecules27103252.'
mla: Asanbaeva, Nargiz B., et al. “Effects of Spiro-Cyclohexane Substitution of
Nitroxyl Biradicals on Dynamic Nuclear Polarization.” Molecules, vol. 27,
no. 10, 2022, p. 3252, doi:10.3390/molecules27103252.
short: N.B. Asanbaeva, L.Y. Gurskaya, Y.F. Polienko, T.V. Rybalova, M.S. Kazantsev,
A.A. Dmitriev, N.P. Gritsan, N. Haro-Mares, T. Gutmann, G. Buntkowsky, E.V. Tretyakov,
E.G. Bagryanskaya, Molecules 27 (2022) 3252.
date_created: 2026-02-07T08:57:49Z
date_updated: 2026-02-20T08:13:29Z
doi: 10.3390/molecules27103252
extern: '1'
intvolume: ' 27'
issue: '10'
language:
- iso: eng
page: '3252'
publication: Molecules
publication_identifier:
issn:
- 1420-3049
status: public
title: Effects of Spiro-Cyclohexane Substitution of Nitroxyl Biradicals on Dynamic
Nuclear Polarization
type: journal_article
user_id: '100715'
volume: 27
year: '2022'
...
---
_id: '64052'
abstract:
- lang: eng
text: Abstract Estuaries are key ecosystems with unique biodiversity and are of
high economic importance. Along the estuaries, variations in environmental parameters,
such as salinity and light penetration, can modify the characteristics of dissolved
organic matter (DOM). Nevertheless, there is still limited information about the
atomic-level transformations of DOM in this ecosystem. Solid-state NMR spectroscopy
provides unique insights into the nature of functional groups in DOM. A major
limitation of this technique is its lack of sensivity, which results in experimental
time of tens of hours for the acquisition of 13C NMR spectra and generally precludes
the observation of 15N nuclei for DOM. We show here how the sensitivity of solid-state
NMR experiments on DOM of Seine estuary can be enhanced using dynamic nuclear
polarization (DNP) under magic-angle spinning. This technique allows the acquisition
of 13C NMR spectra of these samples in few minutes, instead of hours for conventional
solid-state NMR. Both conventional and DNP-enhanced 13C NMR spectra indicate that
the 13C local environments in DOM are not strongly modified along the Seine estuary.
Furthermore, the sensitivity gain provided by the DNP allows the detection of
15N NMR signal of DOM, in spite of the low nitrogen content. These spectra reveal
that the majority of nitrogen is in the amide form in these DOM samples and show
an increased disorder around these amide groups near the mouth of the Seine.
author:
- first_name: Florian
full_name: Venel, Florian
last_name: Venel
- first_name: Hiroki
full_name: Nagashima, Hiroki
last_name: Nagashima
- first_name: Andrew G. M.
full_name: Rankin, Andrew G. M.
last_name: Rankin
- first_name: Christelle
full_name: Anquetil, Christelle
last_name: Anquetil
- first_name: Vytautas
full_name: Klimavicius, Vytautas
last_name: Klimavicius
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Sylvie
full_name: Derenne, Sylvie
last_name: Derenne
- first_name: Olivier
full_name: Lafon, Olivier
last_name: Lafon
- first_name: Arnaud
full_name: Huguet, Arnaud
last_name: Huguet
- first_name: Frédérique
full_name: Pourpoint, Frédérique
last_name: Pourpoint
citation:
ama: Venel F, Nagashima H, Rankin AGM, et al. Characterization of Functional Groups
in Estuarine Dissolved Organic Matter by DNP-enhanced 15N and 13C Solid-State
NMR. Chemphyschem. 2021;22(18):1907–1913. doi:10.1002/cphc.202100334
apa: Venel, F., Nagashima, H., Rankin, A. G. M., Anquetil, C., Klimavicius, V.,
Gutmann, T., Buntkowsky, G., Derenne, S., Lafon, O., Huguet, A., & Pourpoint,
F. (2021). Characterization of Functional Groups in Estuarine Dissolved Organic
Matter by DNP-enhanced 15N and 13C Solid-State NMR. Chemphyschem, 22(18),
1907–1913. https://doi.org/10.1002/cphc.202100334
bibtex: '@article{Venel_Nagashima_Rankin_Anquetil_Klimavicius_Gutmann_Buntkowsky_Derenne_Lafon_Huguet_et
al._2021, title={Characterization of Functional Groups in Estuarine Dissolved
Organic Matter by DNP-enhanced 15N and 13C Solid-State NMR}, volume={22}, DOI={10.1002/cphc.202100334}, number={18},
journal={Chemphyschem}, publisher={John Wiley & Sons, Ltd}, author={Venel,
Florian and Nagashima, Hiroki and Rankin, Andrew G. M. and Anquetil, Christelle
and Klimavicius, Vytautas and Gutmann, Torsten and Buntkowsky, Gerd and Derenne,
Sylvie and Lafon, Olivier and Huguet, Arnaud and et al.}, year={2021}, pages={1907–1913}
}'
chicago: 'Venel, Florian, Hiroki Nagashima, Andrew G. M. Rankin, Christelle Anquetil,
Vytautas Klimavicius, Torsten Gutmann, Gerd Buntkowsky, et al. “Characterization
of Functional Groups in Estuarine Dissolved Organic Matter by DNP-Enhanced 15N
and 13C Solid-State NMR.” Chemphyschem 22, no. 18 (2021): 1907–1913. https://doi.org/10.1002/cphc.202100334.'
ieee: 'F. Venel et al., “Characterization of Functional Groups in Estuarine
Dissolved Organic Matter by DNP-enhanced 15N and 13C Solid-State NMR,” Chemphyschem,
vol. 22, no. 18, pp. 1907–1913, 2021, doi: 10.1002/cphc.202100334.'
mla: Venel, Florian, et al. “Characterization of Functional Groups in Estuarine
Dissolved Organic Matter by DNP-Enhanced 15N and 13C Solid-State NMR.” Chemphyschem,
vol. 22, no. 18, John Wiley & Sons, Ltd, 2021, pp. 1907–1913, doi:10.1002/cphc.202100334.
short: F. Venel, H. Nagashima, A.G.M. Rankin, C. Anquetil, V. Klimavicius, T. Gutmann,
G. Buntkowsky, S. Derenne, O. Lafon, A. Huguet, F. Pourpoint, Chemphyschem 22
(2021) 1907–1913.
date_created: 2026-02-07T16:14:11Z
date_updated: 2026-02-17T16:12:56Z
doi: 10.1002/cphc.202100334
extern: '1'
intvolume: ' 22'
issue: '18'
keyword:
- dynamic nuclear polarization
- 13C
- 15N
- dissolved organic matter
- Seine estuary
language:
- iso: eng
page: 1907–1913
publication: Chemphyschem
publication_identifier:
issn:
- 1439-4235; 1439-7641
publisher: John Wiley & Sons, Ltd
status: public
title: Characterization of Functional Groups in Estuarine Dissolved Organic Matter
by DNP-enhanced 15N and 13C Solid-State NMR
type: journal_article
user_id: '100715'
volume: 22
year: '2021'
...
---
_id: '64051'
abstract:
- lang: eng
text: The efficiency of dynamic nuclear polarization (DNP) enhanced 19F MAS NMR
spectroscopy without 19F-containing solvents and matrices, which transport polarization
via 19F–19F spin diffusion, is demonstrated. By preventing solvent and matrix
signals respectively masking the corresponding resonances, this enables the detection
of fluorinated target molecules in nanomolar amounts. As model compound, 1,3,5-tris(2-fluoro-2-methylpropionylamino)benzene
(F-BTA) is investigated in a frozen 1,1,2,2-tetrachloroethane (TCE) solution and
incorporated into a matrix of isotactic polypropylene (i-PP). While the polarizing
agent is homogeneously dissolved within the frozen solution, for the i-PP/F-BTA
blend, it is distributed via the incipient wetness impregnation (IWI) technique.
For the frozen solutions with an F-BTA concentration of 187.5 mM an εon/off of
260 was obtained. For F-BTA concentrations of 10 and 2.5 mM the sensitivity trend
suggests even higher DNP gains. The substantial enhancements could be achieved
by direct polarization transfer over distances up to at least 20 Å, derived from
a simple geometric model assuming a homogeneous solution, engaging a large part
of the sample volume. Cross-polarization (CP) to 13C nuclei allowed selection
of the NMR spectroscopic resonances of the minority species in the i-PP/F-BTA
blend suppressing the otherwise dominating resonances of the IWI solvent and the
polymer matrix. The possibility of exciting 19F via DNP directly and of transferring
the polarization to other heteronuclei within close proximity enables spatial
spectral editing to clear up spectra otherwise crowded by matrix and solvent signals.
We thus expect direct polarization transfer techniques for DNP enhanced NMR spectroscopy
to become more important in the future.
author:
- first_name: Kasper P.
full_name: van der Zwan, Kasper P.
last_name: van der Zwan
- first_name: Wiebke
full_name: Riedel, Wiebke
last_name: Riedel
- first_name: Fabien
full_name: Aussenac, Fabien
last_name: Aussenac
- first_name: Christian
full_name: Reiter, Christian
last_name: Reiter
- first_name: Klaus
full_name: Kreger, Klaus
last_name: Kreger
- first_name: Hans-Werner
full_name: Schmidt, Hans-Werner
last_name: Schmidt
- first_name: Thomas
full_name: Risse, Thomas
last_name: Risse
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Jürgen
full_name: Senker, Jürgen
last_name: Senker
citation:
ama: 'van der Zwan KP, Riedel W, Aussenac F, et al. 19F MAS DNP for Probing Molecules
in Nanomolar Concentrations: Direct Polarization as Key for Solid-State NMR Spectra
without Solvent and Matrix Signals. Journal of Physical Chemistry C. 2021;125(13):7287–7296.
doi:10.1021/acs.jpcc.1c01167'
apa: 'van der Zwan, K. P., Riedel, W., Aussenac, F., Reiter, C., Kreger, K., Schmidt,
H.-W., Risse, T., Gutmann, T., & Senker, J. (2021). 19F MAS DNP for Probing
Molecules in Nanomolar Concentrations: Direct Polarization as Key for Solid-State
NMR Spectra without Solvent and Matrix Signals. Journal of Physical Chemistry
C, 125(13), 7287–7296. https://doi.org/10.1021/acs.jpcc.1c01167'
bibtex: '@article{van der Zwan_Riedel_Aussenac_Reiter_Kreger_Schmidt_Risse_Gutmann_Senker_2021,
title={19F MAS DNP for Probing Molecules in Nanomolar Concentrations: Direct Polarization
as Key for Solid-State NMR Spectra without Solvent and Matrix Signals}, volume={125},
DOI={10.1021/acs.jpcc.1c01167},
number={13}, journal={Journal of Physical Chemistry C}, publisher={American Chemical
Society}, author={van der Zwan, Kasper P. and Riedel, Wiebke and Aussenac, Fabien
and Reiter, Christian and Kreger, Klaus and Schmidt, Hans-Werner and Risse, Thomas
and Gutmann, Torsten and Senker, Jürgen}, year={2021}, pages={7287–7296} }'
chicago: 'Zwan, Kasper P. van der, Wiebke Riedel, Fabien Aussenac, Christian Reiter,
Klaus Kreger, Hans-Werner Schmidt, Thomas Risse, Torsten Gutmann, and Jürgen Senker.
“19F MAS DNP for Probing Molecules in Nanomolar Concentrations: Direct Polarization
as Key for Solid-State NMR Spectra without Solvent and Matrix Signals.” Journal
of Physical Chemistry C 125, no. 13 (2021): 7287–7296. https://doi.org/10.1021/acs.jpcc.1c01167.'
ieee: 'K. P. van der Zwan et al., “19F MAS DNP for Probing Molecules in Nanomolar
Concentrations: Direct Polarization as Key for Solid-State NMR Spectra without
Solvent and Matrix Signals,” Journal of Physical Chemistry C, vol. 125,
no. 13, pp. 7287–7296, 2021, doi: 10.1021/acs.jpcc.1c01167.'
mla: 'van der Zwan, Kasper P., et al. “19F MAS DNP for Probing Molecules in Nanomolar
Concentrations: Direct Polarization as Key for Solid-State NMR Spectra without
Solvent and Matrix Signals.” Journal of Physical Chemistry C, vol. 125,
no. 13, American Chemical Society, 2021, pp. 7287–7296, doi:10.1021/acs.jpcc.1c01167.'
short: K.P. van der Zwan, W. Riedel, F. Aussenac, C. Reiter, K. Kreger, H.-W. Schmidt,
T. Risse, T. Gutmann, J. Senker, Journal of Physical Chemistry C 125 (2021) 7287–7296.
date_created: 2026-02-07T16:13:55Z
date_updated: 2026-02-17T16:12:59Z
doi: 10.1021/acs.jpcc.1c01167
extern: '1'
intvolume: ' 125'
issue: '13'
language:
- iso: eng
page: 7287–7296
publication: Journal of Physical Chemistry C
publication_identifier:
issn:
- 1932-7447
publisher: American Chemical Society
status: public
title: '19F MAS DNP for Probing Molecules in Nanomolar Concentrations: Direct Polarization
as Key for Solid-State NMR Spectra without Solvent and Matrix Signals'
type: journal_article
user_id: '100715'
volume: 125
year: '2021'
...
---
_id: '64046'
abstract:
- lang: eng
text: The synthesis of a novel immobilized Wilkinson’s catalyst [SiO2∼PvPy-Wilk]
is presented. The support material of this catalyst consists of silica particles
that are modified with polymer brushes carrying pyridyl moieties that enable the
coordination of Wilkinson’s catalyst. The synthesis of this catalyst is monitored
by 1D and 2D multinuclear solid-state NMR techniques to confirm the success of
the immobilization. The [SiO2∼PvPy-Wilk] catalyst is then tested in the hydrogenation
of styrene, and its reusability is inspected showing that significant structural
changes after several reaction cycles yield an activation of the catalyst. Finally,
the catalyst is tested in PHIP experiments giving rise to about 200-fold enhancement
of the signals of the hydrogenation product ethylbenzene.
author:
- first_name: Mohamad
full_name: Srour, Mohamad
last_name: Srour
- first_name: Sara
full_name: Hadjiali, Sara
last_name: Hadjiali
- first_name: Kai
full_name: Brunnengräber, Kai
last_name: Brunnengräber
- first_name: Heiko
full_name: Weidler, Heiko
last_name: Weidler
- first_name: Yeping
full_name: Xu, Yeping
last_name: Xu
- first_name: Hergen
full_name: Breitzke, Hergen
last_name: Breitzke
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
citation:
ama: 'Srour M, Hadjiali S, Brunnengräber K, et al. A Novel Wilkinson’s Type Silica
Supported Polymer Catalyst: Insights from Solid-State NMR and Hyperpolarization
Techniques. Journal of Physical Chemistry C. 2021;125(13):7178–7187. doi:10.1021/acs.jpcc.1c00112'
apa: 'Srour, M., Hadjiali, S., Brunnengräber, K., Weidler, H., Xu, Y., Breitzke,
H., Gutmann, T., & Buntkowsky, G. (2021). A Novel Wilkinson’s Type Silica
Supported Polymer Catalyst: Insights from Solid-State NMR and Hyperpolarization
Techniques. Journal of Physical Chemistry C, 125(13), 7178–7187.
https://doi.org/10.1021/acs.jpcc.1c00112'
bibtex: '@article{Srour_Hadjiali_Brunnengräber_Weidler_Xu_Breitzke_Gutmann_Buntkowsky_2021,
title={A Novel Wilkinson’s Type Silica Supported Polymer Catalyst: Insights from
Solid-State NMR and Hyperpolarization Techniques}, volume={125}, DOI={10.1021/acs.jpcc.1c00112},
number={13}, journal={Journal of Physical Chemistry C}, publisher={American Chemical
Society}, author={Srour, Mohamad and Hadjiali, Sara and Brunnengräber, Kai and
Weidler, Heiko and Xu, Yeping and Breitzke, Hergen and Gutmann, Torsten and Buntkowsky,
Gerd}, year={2021}, pages={7178–7187} }'
chicago: 'Srour, Mohamad, Sara Hadjiali, Kai Brunnengräber, Heiko Weidler, Yeping
Xu, Hergen Breitzke, Torsten Gutmann, and Gerd Buntkowsky. “A Novel Wilkinson’s
Type Silica Supported Polymer Catalyst: Insights from Solid-State NMR and Hyperpolarization
Techniques.” Journal of Physical Chemistry C 125, no. 13 (2021): 7178–7187.
https://doi.org/10.1021/acs.jpcc.1c00112.'
ieee: 'M. Srour et al., “A Novel Wilkinson’s Type Silica Supported Polymer
Catalyst: Insights from Solid-State NMR and Hyperpolarization Techniques,” Journal
of Physical Chemistry C, vol. 125, no. 13, pp. 7178–7187, 2021, doi: 10.1021/acs.jpcc.1c00112.'
mla: 'Srour, Mohamad, et al. “A Novel Wilkinson’s Type Silica Supported Polymer
Catalyst: Insights from Solid-State NMR and Hyperpolarization Techniques.” Journal
of Physical Chemistry C, vol. 125, no. 13, American Chemical Society, 2021,
pp. 7178–7187, doi:10.1021/acs.jpcc.1c00112.'
short: M. Srour, S. Hadjiali, K. Brunnengräber, H. Weidler, Y. Xu, H. Breitzke,
T. Gutmann, G. Buntkowsky, Journal of Physical Chemistry C 125 (2021) 7178–7187.
date_created: 2026-02-07T16:12:28Z
date_updated: 2026-02-17T16:13:08Z
doi: 10.1021/acs.jpcc.1c00112
extern: '1'
intvolume: ' 125'
issue: '13'
language:
- iso: eng
page: 7178–7187
publication: Journal of Physical Chemistry C
publication_identifier:
issn:
- 1932-7447
publisher: American Chemical Society
status: public
title: 'A Novel Wilkinson’s Type Silica Supported Polymer Catalyst: Insights from
Solid-State NMR and Hyperpolarization Techniques'
type: journal_article
user_id: '100715'
volume: 125
year: '2021'
...
---
_id: '64032'
abstract:
- lang: eng
text: Ruthenium nanoparticles (Ru NPs) stabilized by bis-diphenylphosphinobutane
(dppb) and surface-saturated with hydrogen have been exposed to gaseous 15NH3
and studied using solid-state 15N CP MAS NMR. Three signals have been observed
at 24.5, −12 and −42 ppm (reference external liquid ammonia) which are assigned
to chemisorbed ammonia species RuNHx. Sample exposure to vacuum or aging leads
to conversion of the 24.5 ppm species into the other ones, a process which is
reversed by re-exposure to hydrogen gas. Exposure to a mixture of 15NH3 and 13CO
leads to the formation of surface bound urea as demonstrated by 15N and 13C CP
MAS NMR. To understand the surface reactions of ammonia and the 15N NMR results,
quantum chemical calculations of the structures, energies and 15N chemical shifts
of ammonia species on Ru6 and Ru55 model clusters have been performed. The calculations
indicate that under the experimental conditions applied, the fractions of RuNH3
and RuNH2 species are similar, independent of the H2 pressure. No RuN and RuNH
species are formed which are calculated to resonate at a lower field than the
signals observed experimentally. However, the 15N chemical shifts of RuNH2 depend
on the number of neighboring surface hydrogens and hence on the H2 pressure. Thus,
the signal at 24.5 ppm is assigned to RuNH2 in a neighborhood rich in surface
hydrogens. RuNH2 depleted in neighboring surface hydrogens and RuNH3 resonated
both in a similar chemical shift range to which the signals at −12 and −42 belong.
A change of the hydrogen pressure then leads to interconversion of hydrogen-rich
and hydrogen-poor neighborhoods of RuNH2 but does not alter the fractions of RuNH3
and RuNH2 according to the calculated stability diagram. Nevertheless, dissociation
of RuNH3 into RuNH2 and surface hydrogen is expected to take place during the
initial ammonia adsorption process and at low H2 pressures and high temperatures.
Finally, some preliminary quantum chemical calculations suggest stepwise binding
of two NH2 groups to adsorbed CO leading to surface bound urea where the oxygen
is coordinated to Ru.
author:
- first_name: Niels
full_name: Rothermel, Niels
last_name: Rothermel
- first_name: Hans-Heinrich
full_name: Limbach, Hans-Heinrich
last_name: Limbach
- first_name: Iker
full_name: Del Rosal, Iker
last_name: Del Rosal
- first_name: Romuald
full_name: Poteau, Romuald
last_name: Poteau
- first_name: Gabriel
full_name: Mencia, Gabriel
last_name: Mencia
- first_name: Bruno
full_name: Chaudret, Bruno
last_name: Chaudret
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
citation:
ama: Rothermel N, Limbach H-H, Del Rosal I, et al. Surface reactions of ammonia
on ruthenium nanoparticles revealed by 15N and 13C solid-state NMR. Catalysis
Science & Technology. 2021;11(13):4509–4520. doi:10.1039/D0CY02476G
apa: Rothermel, N., Limbach, H.-H., Del Rosal, I., Poteau, R., Mencia, G., Chaudret,
B., Buntkowsky, G., & Gutmann, T. (2021). Surface reactions of ammonia on
ruthenium nanoparticles revealed by 15N and 13C solid-state NMR. Catalysis
Science & Technology, 11(13), 4509–4520. https://doi.org/10.1039/D0CY02476G
bibtex: '@article{Rothermel_Limbach_Del Rosal_Poteau_Mencia_Chaudret_Buntkowsky_Gutmann_2021,
title={Surface reactions of ammonia on ruthenium nanoparticles revealed by 15N
and 13C solid-state NMR}, volume={11}, DOI={10.1039/D0CY02476G},
number={13}, journal={Catalysis Science & Technology}, publisher={The Royal
Society of Chemistry}, author={Rothermel, Niels and Limbach, Hans-Heinrich and
Del Rosal, Iker and Poteau, Romuald and Mencia, Gabriel and Chaudret, Bruno and
Buntkowsky, Gerd and Gutmann, Torsten}, year={2021}, pages={4509–4520} }'
chicago: 'Rothermel, Niels, Hans-Heinrich Limbach, Iker Del Rosal, Romuald Poteau,
Gabriel Mencia, Bruno Chaudret, Gerd Buntkowsky, and Torsten Gutmann. “Surface
Reactions of Ammonia on Ruthenium Nanoparticles Revealed by 15N and 13C Solid-State
NMR.” Catalysis Science & Technology 11, no. 13 (2021): 4509–4520.
https://doi.org/10.1039/D0CY02476G.'
ieee: 'N. Rothermel et al., “Surface reactions of ammonia on ruthenium nanoparticles
revealed by 15N and 13C solid-state NMR,” Catalysis Science & Technology,
vol. 11, no. 13, pp. 4509–4520, 2021, doi: 10.1039/D0CY02476G.'
mla: Rothermel, Niels, et al. “Surface Reactions of Ammonia on Ruthenium Nanoparticles
Revealed by 15N and 13C Solid-State NMR.” Catalysis Science & Technology,
vol. 11, no. 13, The Royal Society of Chemistry, 2021, pp. 4509–4520, doi:10.1039/D0CY02476G.
short: N. Rothermel, H.-H. Limbach, I. Del Rosal, R. Poteau, G. Mencia, B. Chaudret,
G. Buntkowsky, T. Gutmann, Catalysis Science & Technology 11 (2021) 4509–4520.
date_created: 2026-02-07T16:06:48Z
date_updated: 2026-02-17T16:13:50Z
doi: 10.1039/D0CY02476G
extern: '1'
intvolume: ' 11'
issue: '13'
language:
- iso: eng
page: 4509–4520
publication: Catalysis Science & Technology
publication_identifier:
issn:
- 2044-4753
publisher: The Royal Society of Chemistry
status: public
title: Surface reactions of ammonia on ruthenium nanoparticles revealed by 15N and
13C solid-state NMR
type: journal_article
user_id: '100715'
volume: 11
year: '2021'
...
---
_id: '64025'
abstract:
- lang: eng
text: Dirhodium(II) complexes such as [Rh2(TFA)4] bound to a functionalized mesoporous
SBA-15 carrier material have proven to be valuable candidates for heterogeneous
catalysis in the field of pharmaceutical synthesis. However, the mechanistic steps
of immobilization by linker molecules containing carboxyl or amine functionalities
remain the subject of discussion. Here we present a theoretical study of possible
mechanistic binding pathways for the [Rh2(TFA)4] complex through model representations
of synthetically investigated linkers, namely n-butylamine and n-butyric acid.
Experimentally proposed intermediates of the immobilization process are investigated
and analyzed by density functional theory calculations to gain insights into structural
properties and the influence of solvation. An evaluation of the thermodynamic
data for all identified intermediates allowed distinguishing between two possible
reaction pathways that are characterized by a first axial complexation of either
n-butyric acid or n-butylamine. In agreement with results from NMR spectroscopy,
singly or doubly n-butylamine-fixated complexes were found to present possible
immobilization products. Initial binding through a carboxy-functionalized linker
is proposed as the most favorable reaction pathway for the formation of the mixed
linker pattern [Rh2(TFA)3]·(n-butylamine)·(n-butyrate). The linkers n-butyric
acid and n-butyrate, respectively, are found to exhibit an unaltered binding affinity
to the dirhodium complex despite their protonation states, indicating invariance
to the acidic environment unlike an immobilization by n-butylamine. These results
present a theoretical framework for the rationalization of observed product distributions
while also providing inspiration and guidance for the preparation of functionalized
heterogeneous SBA-15/dirhodium catalyst systems.
author:
- first_name: Dennis S.
full_name: Pietruschka, Dennis S.
last_name: Pietruschka
- first_name: Bharti
full_name: Kumari, Bharti
last_name: Kumari
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Doreen
full_name: Mollenhauer, Doreen
last_name: Mollenhauer
citation:
ama: 'Pietruschka DS, Kumari B, Buntkowsky G, Gutmann T, Mollenhauer D. Mechanism
of Heterogenization of Dirhodium Catalysts: Insights from DFT Calculations. Inorganic
Chemistry. 2021;60(9):6239–6248. doi:10.1021/acs.inorgchem.0c03712'
apa: 'Pietruschka, D. S., Kumari, B., Buntkowsky, G., Gutmann, T., & Mollenhauer,
D. (2021). Mechanism of Heterogenization of Dirhodium Catalysts: Insights from
DFT Calculations. Inorganic Chemistry, 60(9), 6239–6248. https://doi.org/10.1021/acs.inorgchem.0c03712'
bibtex: '@article{Pietruschka_Kumari_Buntkowsky_Gutmann_Mollenhauer_2021, title={Mechanism
of Heterogenization of Dirhodium Catalysts: Insights from DFT Calculations}, volume={60},
DOI={10.1021/acs.inorgchem.0c03712},
number={9}, journal={Inorganic Chemistry}, publisher={American Chemical Society},
author={Pietruschka, Dennis S. and Kumari, Bharti and Buntkowsky, Gerd and Gutmann,
Torsten and Mollenhauer, Doreen}, year={2021}, pages={6239–6248} }'
chicago: 'Pietruschka, Dennis S., Bharti Kumari, Gerd Buntkowsky, Torsten Gutmann,
and Doreen Mollenhauer. “Mechanism of Heterogenization of Dirhodium Catalysts:
Insights from DFT Calculations.” Inorganic Chemistry 60, no. 9 (2021):
6239–6248. https://doi.org/10.1021/acs.inorgchem.0c03712.'
ieee: 'D. S. Pietruschka, B. Kumari, G. Buntkowsky, T. Gutmann, and D. Mollenhauer,
“Mechanism of Heterogenization of Dirhodium Catalysts: Insights from DFT Calculations,”
Inorganic Chemistry, vol. 60, no. 9, pp. 6239–6248, 2021, doi: 10.1021/acs.inorgchem.0c03712.'
mla: 'Pietruschka, Dennis S., et al. “Mechanism of Heterogenization of Dirhodium
Catalysts: Insights from DFT Calculations.” Inorganic Chemistry, vol. 60,
no. 9, American Chemical Society, 2021, pp. 6239–6248, doi:10.1021/acs.inorgchem.0c03712.'
short: D.S. Pietruschka, B. Kumari, G. Buntkowsky, T. Gutmann, D. Mollenhauer, Inorganic
Chemistry 60 (2021) 6239–6248.
date_created: 2026-02-07T16:04:53Z
date_updated: 2026-02-17T16:14:13Z
doi: 10.1021/acs.inorgchem.0c03712
extern: '1'
intvolume: ' 60'
issue: '9'
language:
- iso: eng
page: 6239–6248
publication: Inorganic Chemistry
publisher: American Chemical Society
status: public
title: 'Mechanism of Heterogenization of Dirhodium Catalysts: Insights from DFT Calculations'
type: journal_article
user_id: '100715'
volume: 60
year: '2021'
...
---
_id: '64027'
abstract:
- lang: eng
text: The biorelevant PyFALGEA oligopeptide ligand, which is selective towards the
epidermal growth factor receptor (EGFR), has been successfully employed as a substrate
in magnetic resonance signal amplification by reversible exchange (SABRE) experiments.
It is demonstrated that PyFALGEA and the iridium catalyst IMes form a PyFALGEA:IMes
molecular complex. The interaction between PyFALGEA:IMes and H-2 results in a
ternary SABRE complex. Selective 1D EXSY experiments reveal that this complex
is labile, which is an essential condition for successful hyperpolarization by
SABRE. Polarization transfer from parahydrogen to PyFALGEA is observed leading
to significant enhancement of the H-1 NMR signals of PyFALGEA. Different iridium
catalysts and peptides are inspected to discuss the influence of their molecular
structures on the efficiency of hyperpolarization. It is observed that PyFALGEA
oligopeptide hyperpolarization is more efficient when an iridium catalyst with
a sterically less demanding NHC ligand system such as IMesBn is employed. Experiments
with shorter analogues of PyFALGEA, that is, PyLGEA and PyEA, show that the bulky
phenylalanine from the PyFALGEA oligopeptide causes steric hindrance in the SABRE
complex, which hampers hyperpolarization with IMes. Finally, a single-scan H-1
NMR SABRE experiment of PyFALGEA with IMesBn revealed a unique pattern of NMR
lines in the hydride region, which can be treated as a fingerprint of this important
oligopeptide.
author:
- first_name: T.
full_name: Ratajczyk, T.
last_name: Ratajczyk
- first_name: G.
full_name: Buntkowsky, G.
last_name: Buntkowsky
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: B.
full_name: Fedorczyk, B.
last_name: Fedorczyk
- first_name: A.
full_name: Mames, A.
last_name: Mames
- first_name: M.
full_name: Pietrzak, M.
last_name: Pietrzak
- first_name: Z.
full_name: Puzio, Z.
last_name: Puzio
- first_name: P. G.
full_name: Szkudlarek, P. G.
last_name: Szkudlarek
citation:
ama: Ratajczyk T, Buntkowsky G, Gutmann T, et al. Magnetic Resonance Signal Amplification
by Reversible Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal
Growth Factor Receptors. ChemBioChem. 2021;22(5):855–860. doi:10.1002/cbic.202000711
apa: Ratajczyk, T., Buntkowsky, G., Gutmann, T., Fedorczyk, B., Mames, A., Pietrzak,
M., Puzio, Z., & Szkudlarek, P. G. (2021). Magnetic Resonance Signal Amplification
by Reversible Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal
Growth Factor Receptors. ChemBioChem, 22(5), 855–860. https://doi.org/10.1002/cbic.202000711
bibtex: '@article{Ratajczyk_Buntkowsky_Gutmann_Fedorczyk_Mames_Pietrzak_Puzio_Szkudlarek_2021,
title={Magnetic Resonance Signal Amplification by Reversible Exchange of Selective
PyFALGEA Oligopeptide Ligands Towards Epidermal Growth Factor Receptors}, volume={22},
DOI={10.1002/cbic.202000711},
number={5}, journal={ChemBioChem}, author={Ratajczyk, T. and Buntkowsky, G. and
Gutmann, Torsten and Fedorczyk, B. and Mames, A. and Pietrzak, M. and Puzio, Z.
and Szkudlarek, P. G.}, year={2021}, pages={855–860} }'
chicago: 'Ratajczyk, T., G. Buntkowsky, Torsten Gutmann, B. Fedorczyk, A. Mames,
M. Pietrzak, Z. Puzio, and P. G. Szkudlarek. “Magnetic Resonance Signal Amplification
by Reversible Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal
Growth Factor Receptors.” ChemBioChem 22, no. 5 (2021): 855–860. https://doi.org/10.1002/cbic.202000711.'
ieee: 'T. Ratajczyk et al., “Magnetic Resonance Signal Amplification by Reversible
Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal Growth Factor
Receptors,” ChemBioChem, vol. 22, no. 5, pp. 855–860, 2021, doi: 10.1002/cbic.202000711.'
mla: Ratajczyk, T., et al. “Magnetic Resonance Signal Amplification by Reversible
Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal Growth Factor
Receptors.” ChemBioChem, vol. 22, no. 5, 2021, pp. 855–860, doi:10.1002/cbic.202000711.
short: T. Ratajczyk, G. Buntkowsky, T. Gutmann, B. Fedorczyk, A. Mames, M. Pietrzak,
Z. Puzio, P.G. Szkudlarek, ChemBioChem 22 (2021) 855–860.
date_created: 2026-02-07T16:05:21Z
date_updated: 2026-02-17T16:14:09Z
doi: 10.1002/cbic.202000711
extern: '1'
intvolume: ' 22'
issue: '5'
language:
- iso: eng
page: 855–860
publication: ChemBioChem
status: public
title: Magnetic Resonance Signal Amplification by Reversible Exchange of Selective
PyFALGEA Oligopeptide Ligands Towards Epidermal Growth Factor Receptors
type: journal_article
user_id: '100715'
volume: 22
year: '2021'
...
---
_id: '64022'
abstract:
- lang: eng
text: High-field dynamic nuclear polarization is a powerful tool for the structural
characterization of species on the surface of porous materials or nanoparticles.
For these studies the main source of polarization are radical-containing solutions
which are added by post-synthesis impregnation of the sample. Although this strategy
is very efficient for a wide variety of materials, the presence of the solvent
may influence the chemistry of functional species of interest. Here we address
the development of a comprehensive strategy for solvent-free DNP enhanced NMR
characterization of functional (target) species on the surface of mesoporous silica
(SBA-15). The strategy includes the partial functionalization of the silica surface
with Carboxy-Proxyl nitroxide radicals and target Fmoc-Glycine functional groups.
As a proof of principle, we have observed for the first time DNP signal enhancements,
using the solvent-free approach, for 13C1H CPMAS signals corresponding to organic
functionalities on the silica surface. DNP enhancements of up to 3.4 were observed
for 13C1H CPMAS, corresponding to an experimental time save of about 12 times.
This observation opens the possibility for the DNP-NMR study of surface functional
groups without the need of a solvent, allowing, for example, the characterization
of catalytic reactions occurring on the surface of mesoporous systems of interest.
For 29Si with direct polarization NMR, up to 8-fold DNP enhancements were obtained.
This 29Si signal enhancement is considerably higher than the obtained with similar
approaches reported in literature. Finally, from DNP enhancement profiles we conclude
that cross-effect is probably the dominant polarization transfer mechanism.
author:
- first_name: Marcos
full_name: Oliveira, Marcos
last_name: Oliveira
- first_name: Kevin
full_name: Herr, Kevin
last_name: Herr
- first_name: Martin
full_name: Brodrecht, Martin
last_name: Brodrecht
- first_name: Nadia B.
full_name: Haro-Mares, Nadia B.
last_name: Haro-Mares
- first_name: Till
full_name: Wissel, Till
last_name: Wissel
- first_name: Vytautas
full_name: Klimavicius, Vytautas
last_name: Klimavicius
- first_name: Hergen
full_name: Breitzke, Hergen
last_name: Breitzke
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
citation:
ama: Oliveira M, Herr K, Brodrecht M, et al. Solvent-free dynamic nuclear polarization
enhancements in organically modified mesoporous silica. Physical Chemistry
Chemical Physics. 2021;23(22):12559–12568. doi:10.1039/D1CP00985K
apa: Oliveira, M., Herr, K., Brodrecht, M., Haro-Mares, N. B., Wissel, T., Klimavicius,
V., Breitzke, H., Gutmann, T., & Buntkowsky, G. (2021). Solvent-free dynamic
nuclear polarization enhancements in organically modified mesoporous silica. Physical
Chemistry Chemical Physics, 23(22), 12559–12568. https://doi.org/10.1039/D1CP00985K
bibtex: '@article{Oliveira_Herr_Brodrecht_Haro-Mares_Wissel_Klimavicius_Breitzke_Gutmann_Buntkowsky_2021,
title={Solvent-free dynamic nuclear polarization enhancements in organically modified
mesoporous silica}, volume={23}, DOI={10.1039/D1CP00985K},
number={22}, journal={Physical Chemistry Chemical Physics}, publisher={The Royal
Society of Chemistry}, author={Oliveira, Marcos and Herr, Kevin and Brodrecht,
Martin and Haro-Mares, Nadia B. and Wissel, Till and Klimavicius, Vytautas and
Breitzke, Hergen and Gutmann, Torsten and Buntkowsky, Gerd}, year={2021}, pages={12559–12568}
}'
chicago: 'Oliveira, Marcos, Kevin Herr, Martin Brodrecht, Nadia B. Haro-Mares, Till
Wissel, Vytautas Klimavicius, Hergen Breitzke, Torsten Gutmann, and Gerd Buntkowsky.
“Solvent-Free Dynamic Nuclear Polarization Enhancements in Organically Modified
Mesoporous Silica.” Physical Chemistry Chemical Physics 23, no. 22 (2021):
12559–12568. https://doi.org/10.1039/D1CP00985K.'
ieee: 'M. Oliveira et al., “Solvent-free dynamic nuclear polarization enhancements
in organically modified mesoporous silica,” Physical Chemistry Chemical Physics,
vol. 23, no. 22, pp. 12559–12568, 2021, doi: 10.1039/D1CP00985K.'
mla: Oliveira, Marcos, et al. “Solvent-Free Dynamic Nuclear Polarization Enhancements
in Organically Modified Mesoporous Silica.” Physical Chemistry Chemical Physics,
vol. 23, no. 22, The Royal Society of Chemistry, 2021, pp. 12559–12568, doi:10.1039/D1CP00985K.
short: M. Oliveira, K. Herr, M. Brodrecht, N.B. Haro-Mares, T. Wissel, V. Klimavicius,
H. Breitzke, T. Gutmann, G. Buntkowsky, Physical Chemistry Chemical Physics 23
(2021) 12559–12568.
date_created: 2026-02-07T16:03:58Z
date_updated: 2026-02-17T16:14:21Z
doi: 10.1039/D1CP00985K
extern: '1'
intvolume: ' 23'
issue: '22'
language:
- iso: eng
page: 12559–12568
publication: Physical Chemistry Chemical Physics
publisher: The Royal Society of Chemistry
status: public
title: Solvent-free dynamic nuclear polarization enhancements in organically modified
mesoporous silica
type: journal_article
user_id: '100715'
volume: 23
year: '2021'
...
---
_id: '64016'
abstract:
- lang: eng
text: Bacterial cellulose (BC) combined with organo-bridged porous silica nanoparticles
offers potential opportunities to develop smart hybrid materials such as advanced
drug delivery nanosystems. This work reports the preparation of bacterial cellulose
membrane (BCM) and their modification by in situ methodology with the organo-bridged
precursor 1,4-bis(triethoxysilyl)benzene (BTEB). BTEB was successfully incorporated
into the BCM, and spherical hybrid silica nanoparticles with heterogeneous particle
size (30–100 nm) and probably porous structure were formed and characterized by
scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier
transform infrared–attenuated total reflectance (FTIR-ATR), thermogravimetric
analysis (TGA), and solid state nuclear magnetic resonance (NMR). We further combined
solid-state NMR with dynamic nuclear polarization (DNP) to achieve sensitivity
enhancement and to selectively enhance the NMR signal of the hydrophobic BTEB
moieties on the BCM surface. This allowed us to get more detailed structural information
about the BTEB–BCM multicomponent material.
author:
- first_name: Andreia S.
full_name: Monteiro, Andreia S.
last_name: Monteiro
- first_name: Marcos
full_name: Oliveira, Marcos
last_name: Oliveira
- first_name: Silvia
full_name: Santagneli, Silvia
last_name: Santagneli
- first_name: Carole
full_name: Carcel, Carole
last_name: Carcel
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Michel Wong Chi
full_name: Man, Michel Wong Chi
last_name: Man
- first_name: Hernane S.
full_name: Barud, Hernane S.
last_name: Barud
- first_name: Sidney J. L.
full_name: Ribeiro, Sidney J. L.
last_name: Ribeiro
citation:
ama: 'Monteiro AS, Oliveira M, Santagneli S, et al. Modification of Bacterial Cellulose
Membrane with 1,4-Bis(triethoxysilyl)benzene: A Thorough Physical–Chemical Characterization
Study. Journal of Physical Chemistry C. 2021;125(8):4498–4508. doi:10.1021/acs.jpcc.0c09837'
apa: 'Monteiro, A. S., Oliveira, M., Santagneli, S., Carcel, C., Gutmann, T., Buntkowsky,
G., Man, M. W. C., Barud, H. S., & Ribeiro, S. J. L. (2021). Modification
of Bacterial Cellulose Membrane with 1,4-Bis(triethoxysilyl)benzene: A Thorough
Physical–Chemical Characterization Study. Journal of Physical Chemistry C,
125(8), 4498–4508. https://doi.org/10.1021/acs.jpcc.0c09837'
bibtex: '@article{Monteiro_Oliveira_Santagneli_Carcel_Gutmann_Buntkowsky_Man_Barud_Ribeiro_2021,
title={Modification of Bacterial Cellulose Membrane with 1,4-Bis(triethoxysilyl)benzene:
A Thorough Physical–Chemical Characterization Study}, volume={125}, DOI={10.1021/acs.jpcc.0c09837},
number={8}, journal={Journal of Physical Chemistry C}, publisher={American Chemical
Society}, author={Monteiro, Andreia S. and Oliveira, Marcos and Santagneli, Silvia
and Carcel, Carole and Gutmann, Torsten and Buntkowsky, Gerd and Man, Michel Wong
Chi and Barud, Hernane S. and Ribeiro, Sidney J. L.}, year={2021}, pages={4498–4508}
}'
chicago: 'Monteiro, Andreia S., Marcos Oliveira, Silvia Santagneli, Carole Carcel,
Torsten Gutmann, Gerd Buntkowsky, Michel Wong Chi Man, Hernane S. Barud, and Sidney
J. L. Ribeiro. “Modification of Bacterial Cellulose Membrane with 1,4-Bis(Triethoxysilyl)Benzene:
A Thorough Physical–Chemical Characterization Study.” Journal of Physical Chemistry
C 125, no. 8 (2021): 4498–4508. https://doi.org/10.1021/acs.jpcc.0c09837.'
ieee: 'A. S. Monteiro et al., “Modification of Bacterial Cellulose Membrane
with 1,4-Bis(triethoxysilyl)benzene: A Thorough Physical–Chemical Characterization
Study,” Journal of Physical Chemistry C, vol. 125, no. 8, pp. 4498–4508,
2021, doi: 10.1021/acs.jpcc.0c09837.'
mla: 'Monteiro, Andreia S., et al. “Modification of Bacterial Cellulose Membrane
with 1,4-Bis(Triethoxysilyl)Benzene: A Thorough Physical–Chemical Characterization
Study.” Journal of Physical Chemistry C, vol. 125, no. 8, American Chemical
Society, 2021, pp. 4498–4508, doi:10.1021/acs.jpcc.0c09837.'
short: A.S. Monteiro, M. Oliveira, S. Santagneli, C. Carcel, T. Gutmann, G. Buntkowsky,
M.W.C. Man, H.S. Barud, S.J.L. Ribeiro, Journal of Physical Chemistry C 125 (2021)
4498–4508.
date_created: 2026-02-07T16:01:29Z
date_updated: 2026-02-17T16:15:10Z
doi: 10.1021/acs.jpcc.0c09837
extern: '1'
intvolume: ' 125'
issue: '8'
language:
- iso: eng
page: 4498–4508
publication: Journal of Physical Chemistry C
publication_identifier:
issn:
- 1932-7447
publisher: American Chemical Society
status: public
title: 'Modification of Bacterial Cellulose Membrane with 1,4-Bis(triethoxysilyl)benzene:
A Thorough Physical–Chemical Characterization Study'
type: journal_article
user_id: '100715'
volume: 125
year: '2021'
...
---
_id: '64015'
abstract:
- lang: eng
text: Periodate oxidation reaction occurring directly on chitin has been neglected
in polysaccharide chemistry so far. Herein, we present the first direct alkaline
periodate oxidation of chitin, which demonstrates at the same time a novel approach
for the preparation of chitin nanocrystals (ChNCs). This oxidation is based on
an unprecedented selective reaction of non-ordered domains of chitin by the dimeric
orthoperiodate ions (H2I2O104−) as the major species in alkaline surroundings.
Nearly 50 wt% of non-ordered regions are dissolved after sequential accelerated
partial deacetylation, periodate oxidation and β-alkoxy fragmentation, which allows
the isolation of up to 50 wt% of uniform anisotropic zwitterionic ChNCs.
author:
- first_name: Peiwen
full_name: Liu, Peiwen
last_name: Liu
- first_name: Huan
full_name: Liu, Huan
last_name: Liu
- first_name: Timmy
full_name: Schäfer, Timmy
last_name: Schäfer
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Holger
full_name: Gibhardt, Holger
last_name: Gibhardt
- first_name: Houjuan
full_name: Qi, Houjuan
last_name: Qi
- first_name: Lin
full_name: Tian, Lin
last_name: Tian
- first_name: Xizhou Cecily
full_name: Zhang, Xizhou Cecily
last_name: Zhang
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
- first_name: Kai
full_name: Zhang, Kai
last_name: Zhang
citation:
ama: Liu P, Liu H, Schäfer T, et al. Unexpected selective alkaline periodate oxidation
of chitin for the isolation of chitin nanocrystals. Green Chemistry. 2021;23(2):745–751.
doi:10.1039/D0GC04054A
apa: Liu, P., Liu, H., Schäfer, T., Gutmann, T., Gibhardt, H., Qi, H., Tian, L.,
Zhang, X. C., Buntkowsky, G., & Zhang, K. (2021). Unexpected selective alkaline
periodate oxidation of chitin for the isolation of chitin nanocrystals. Green
Chemistry, 23(2), 745–751. https://doi.org/10.1039/D0GC04054A
bibtex: '@article{Liu_Liu_Schäfer_Gutmann_Gibhardt_Qi_Tian_Zhang_Buntkowsky_Zhang_2021,
title={Unexpected selective alkaline periodate oxidation of chitin for the isolation
of chitin nanocrystals}, volume={23}, DOI={10.1039/D0GC04054A},
number={2}, journal={Green Chemistry}, publisher={The Royal Society of Chemistry},
author={Liu, Peiwen and Liu, Huan and Schäfer, Timmy and Gutmann, Torsten and
Gibhardt, Holger and Qi, Houjuan and Tian, Lin and Zhang, Xizhou Cecily and Buntkowsky,
Gerd and Zhang, Kai}, year={2021}, pages={745–751} }'
chicago: 'Liu, Peiwen, Huan Liu, Timmy Schäfer, Torsten Gutmann, Holger Gibhardt,
Houjuan Qi, Lin Tian, Xizhou Cecily Zhang, Gerd Buntkowsky, and Kai Zhang. “Unexpected
Selective Alkaline Periodate Oxidation of Chitin for the Isolation of Chitin Nanocrystals.”
Green Chemistry 23, no. 2 (2021): 745–751. https://doi.org/10.1039/D0GC04054A.'
ieee: 'P. Liu et al., “Unexpected selective alkaline periodate oxidation
of chitin for the isolation of chitin nanocrystals,” Green Chemistry, vol.
23, no. 2, pp. 745–751, 2021, doi: 10.1039/D0GC04054A.'
mla: Liu, Peiwen, et al. “Unexpected Selective Alkaline Periodate Oxidation of Chitin
for the Isolation of Chitin Nanocrystals.” Green Chemistry, vol. 23, no.
2, The Royal Society of Chemistry, 2021, pp. 745–751, doi:10.1039/D0GC04054A.
short: P. Liu, H. Liu, T. Schäfer, T. Gutmann, H. Gibhardt, H. Qi, L. Tian, X.C.
Zhang, G. Buntkowsky, K. Zhang, Green Chemistry 23 (2021) 745–751.
date_created: 2026-02-07T16:01:08Z
date_updated: 2026-02-17T16:15:12Z
doi: 10.1039/D0GC04054A
extern: '1'
intvolume: ' 23'
issue: '2'
language:
- iso: eng
page: 745–751
publication: Green Chemistry
publisher: The Royal Society of Chemistry
status: public
title: Unexpected selective alkaline periodate oxidation of chitin for the isolation
of chitin nanocrystals
type: journal_article
user_id: '100715'
volume: 23
year: '2021'
...
---
_id: '64006'
abstract:
- lang: eng
text: Three chiral dirhodium coordination polymers Rh2–Ln (n = 1–3) have been synthesized
via ligand exchange between dirhodium trifluoroacetate Rh2(TFA)4 and differently
sized chiral dicarboxylic acids derived from l-tert-leucine. SEM images indicate
that the Rh2–Ln (n = 1–3) polymers have a lamellar structure. XPS data demonstrate
that the oxidation state of rhodium in the dirhodium nodes is maintained during
the synthesis of the polymers. The coordination polymers have been further characterized
by FTIR, 1H → 13C CP MAS NMR and 19F MAS NMR spectroscopy to prove the formation
of polymers via ligand exchange. Although the quantitative 19F MAS NMR spectra
reveal incomplete ligand substitution in the coordination polymers, these catalysts
show excellent activity and selectivity in the asymmetric cyclopropanation reaction
between styrene and diazooxindole. In particular, the enantioselectivity has been
significantly improved compared with previously designed dirhodium coordination
polymers, which were synthesized from aromatic dicarboxylic acids derived from
l-phenylalanine. Meanwhile, the dirhodium polymers can be easily recycled five
times without significant reduction in their catalytic efficiency.
author:
- first_name: Zhenzhong
full_name: Li, Zhenzhong
last_name: Li
- first_name: Lorenz
full_name: Rösler, Lorenz
last_name: Rösler
- first_name: Till
full_name: Wissel, Till
last_name: Wissel
- first_name: Hergen
full_name: Breitzke, Hergen
last_name: Breitzke
- first_name: Kathrin
full_name: Hofmann, Kathrin
last_name: Hofmann
- first_name: Hans-Heinrich
full_name: Limbach, Hans-Heinrich
last_name: Limbach
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
citation:
ama: Li Z, Rösler L, Wissel T, et al. Design and characterization of novel dirhodium
coordination polymers – the impact of ligand size on selectivity in asymmetric
cyclopropanation. Catalysis Science & Technology. 2021;11(10):3481–3492.
doi:10.1039/D1CY00109D
apa: Li, Z., Rösler, L., Wissel, T., Breitzke, H., Hofmann, K., Limbach, H.-H.,
Gutmann, T., & Buntkowsky, G. (2021). Design and characterization of novel
dirhodium coordination polymers – the impact of ligand size on selectivity in
asymmetric cyclopropanation. Catalysis Science & Technology, 11(10),
3481–3492. https://doi.org/10.1039/D1CY00109D
bibtex: '@article{Li_Rösler_Wissel_Breitzke_Hofmann_Limbach_Gutmann_Buntkowsky_2021,
title={Design and characterization of novel dirhodium coordination polymers –
the impact of ligand size on selectivity in asymmetric cyclopropanation}, volume={11},
DOI={10.1039/D1CY00109D}, number={10},
journal={Catalysis Science & Technology}, publisher={The Royal Society of
Chemistry}, author={Li, Zhenzhong and Rösler, Lorenz and Wissel, Till and Breitzke,
Hergen and Hofmann, Kathrin and Limbach, Hans-Heinrich and Gutmann, Torsten and
Buntkowsky, Gerd}, year={2021}, pages={3481–3492} }'
chicago: 'Li, Zhenzhong, Lorenz Rösler, Till Wissel, Hergen Breitzke, Kathrin Hofmann,
Hans-Heinrich Limbach, Torsten Gutmann, and Gerd Buntkowsky. “Design and Characterization
of Novel Dirhodium Coordination Polymers – the Impact of Ligand Size on Selectivity
in Asymmetric Cyclopropanation.” Catalysis Science & Technology 11,
no. 10 (2021): 3481–3492. https://doi.org/10.1039/D1CY00109D.'
ieee: 'Z. Li et al., “Design and characterization of novel dirhodium coordination
polymers – the impact of ligand size on selectivity in asymmetric cyclopropanation,”
Catalysis Science & Technology, vol. 11, no. 10, pp. 3481–3492, 2021,
doi: 10.1039/D1CY00109D.'
mla: Li, Zhenzhong, et al. “Design and Characterization of Novel Dirhodium Coordination
Polymers – the Impact of Ligand Size on Selectivity in Asymmetric Cyclopropanation.”
Catalysis Science & Technology, vol. 11, no. 10, The Royal Society
of Chemistry, 2021, pp. 3481–3492, doi:10.1039/D1CY00109D.
short: Z. Li, L. Rösler, T. Wissel, H. Breitzke, K. Hofmann, H.-H. Limbach, T. Gutmann,
G. Buntkowsky, Catalysis Science & Technology 11 (2021) 3481–3492.
date_created: 2026-02-07T15:55:39Z
date_updated: 2026-02-17T16:15:33Z
doi: 10.1039/D1CY00109D
extern: '1'
intvolume: ' 11'
issue: '10'
language:
- iso: eng
page: 3481–3492
publication: Catalysis Science & Technology
publication_identifier:
issn:
- 2044-4753
publisher: The Royal Society of Chemistry
status: public
title: Design and characterization of novel dirhodium coordination polymers – the
impact of ligand size on selectivity in asymmetric cyclopropanation
type: journal_article
user_id: '100715'
volume: 11
year: '2021'
...
---
_id: '64005'
abstract:
- lang: eng
text: A novel immobilized chiral dirhodium catalyst, Rh2(S-PTTL)3(S-PTTL-linker)∼SBA-15
(8), has been prepared via click reaction of azide-groups on functionalized SBA-15
with the dirhodium complex Rh2(S-PTTL)3(S-PTTL-alkyne) (6) containing an alkyne
moiety. During the synthesis of this complex, one chiral ligand of the parent
Rh2(S-PTTL)4 catalyst is exchanged with an analogous chiral ligand system containing
an alkyne moiety, which to a great extent maintains the intrinsic catalytic performance
of the catalyst. The heterogeneous dirhodium catalyst is characterized by FT-IR
and 13C solid-state NMR to validate the successful immobilization. The catalytic
performance of the heterogeneous catalyst 8 is investigated in the asymmetric
cyclopropanation of 3-diazooxindole with different aryl alkenes that form spiro-cyclopropyloxindoles
which serve as precursors for pharmaceuticals. The resulting heterogeneous catalyst
shows high catalytic activity and significant enantioselectivity. Importantly,
it can be readily recovered and reused at least four times without significant
loss of its catalytic performance.
author:
- first_name: Zhenzhong
full_name: Li, Zhenzhong
last_name: Li
- first_name: Lorenz
full_name: Rösler, Lorenz
last_name: Rösler
- first_name: Till
full_name: Wissel, Till
last_name: Wissel
- first_name: Hergen
full_name: Breitzke, Hergen
last_name: Breitzke
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Gerd
full_name: Buntkowsky, Gerd
last_name: Buntkowsky
citation:
ama: 'Li Z, Rösler L, Wissel T, Breitzke H, Gutmann T, Buntkowsky G. Immobilization
of a chiral dirhodium catalyst on SBA-15 via click-chemistry: Application in the
asymmetric cyclopropanation of 3-diazooxindole with aryl alkenes. Journal of
CO2 Utilization. 2021;52:101682. doi:10.1016/j.jcou.2021.101682'
apa: 'Li, Z., Rösler, L., Wissel, T., Breitzke, H., Gutmann, T., & Buntkowsky,
G. (2021). Immobilization of a chiral dirhodium catalyst on SBA-15 via click-chemistry:
Application in the asymmetric cyclopropanation of 3-diazooxindole with aryl alkenes.
Journal of CO2 Utilization, 52, 101682. https://doi.org/10.1016/j.jcou.2021.101682'
bibtex: '@article{Li_Rösler_Wissel_Breitzke_Gutmann_Buntkowsky_2021, title={Immobilization
of a chiral dirhodium catalyst on SBA-15 via click-chemistry: Application in the
asymmetric cyclopropanation of 3-diazooxindole with aryl alkenes}, volume={52},
DOI={10.1016/j.jcou.2021.101682},
journal={Journal of CO2 Utilization}, author={Li, Zhenzhong and Rösler, Lorenz
and Wissel, Till and Breitzke, Hergen and Gutmann, Torsten and Buntkowsky, Gerd},
year={2021}, pages={101682} }'
chicago: 'Li, Zhenzhong, Lorenz Rösler, Till Wissel, Hergen Breitzke, Torsten Gutmann,
and Gerd Buntkowsky. “Immobilization of a Chiral Dirhodium Catalyst on SBA-15
via Click-Chemistry: Application in the Asymmetric Cyclopropanation of 3-Diazooxindole
with Aryl Alkenes.” Journal of CO2 Utilization 52 (2021): 101682. https://doi.org/10.1016/j.jcou.2021.101682.'
ieee: 'Z. Li, L. Rösler, T. Wissel, H. Breitzke, T. Gutmann, and G. Buntkowsky,
“Immobilization of a chiral dirhodium catalyst on SBA-15 via click-chemistry:
Application in the asymmetric cyclopropanation of 3-diazooxindole with aryl alkenes,”
Journal of CO2 Utilization, vol. 52, p. 101682, 2021, doi: 10.1016/j.jcou.2021.101682.'
mla: 'Li, Zhenzhong, et al. “Immobilization of a Chiral Dirhodium Catalyst on SBA-15
via Click-Chemistry: Application in the Asymmetric Cyclopropanation of 3-Diazooxindole
with Aryl Alkenes.” Journal of CO2 Utilization, vol. 52, 2021, p. 101682,
doi:10.1016/j.jcou.2021.101682.'
short: Z. Li, L. Rösler, T. Wissel, H. Breitzke, T. Gutmann, G. Buntkowsky, Journal
of CO2 Utilization 52 (2021) 101682.
date_created: 2026-02-07T15:55:18Z
date_updated: 2026-02-17T16:15:35Z
doi: 10.1016/j.jcou.2021.101682
extern: '1'
intvolume: ' 52'
keyword:
- immobilized catalyst
- asymmetric cyclopropanation
- Chiral dirhodium
language:
- iso: eng
page: '101682'
publication: Journal of CO2 Utilization
status: public
title: 'Immobilization of a chiral dirhodium catalyst on SBA-15 via click-chemistry:
Application in the asymmetric cyclopropanation of 3-diazooxindole with aryl alkenes'
type: journal_article
user_id: '100715'
volume: 52
year: '2021'
...
---
_id: '63993'
abstract:
- lang: eng
text: A synthetic strategy to β-silylphospholes with three methoxy, ethoxy, chloro,
hydrido, or phenyl substituents at silicon has been developed, starting from trimethoxy,
triethoxy, or triphenyl silyl substituted phenyl phosphanides and 1,4-diphenyl-1,3-butadiyne.
These trifunctional silylphospholes were attached to the surface of uniform spheric
silica particles (15 μm) and, for comparison, to a polyhedral silsesquioxane (POSS)–trisilanol
as a molecular model to explore their luminescent properties in comparison with
the free phospholes. Density functional theory calculations were performed to
investigate any electronic perturbation of the phosphole system by the trifunctional
silyl anchoring unit. For the immobilized phospholes, cross-polarization magic-angle-spinning
NMR measurements (13C, 29Si, and 31P) were carried out to explore the bonding
situation to the silica surface. Thermogravimetric analysis and X-ray photoelectron
spectroscopy measurements were performed to approximate the amount of phospholes
covering the silica surface. Identity and purity of all novel phospholes have
been established with standard techniques (multinuclear NMR, mass spectrometry,
and elemental analysis) and X-ray diffraction for the POSS derivative.
author:
- first_name: Dieter
full_name: Klintuch, Dieter
last_name: Klintuch
- first_name: Mark V.
full_name: Höfler, Mark V.
last_name: Höfler
- first_name: Till
full_name: Wissel, Till
last_name: Wissel
- first_name: Clemens
full_name: Bruhn, Clemens
last_name: Bruhn
- first_name: Torsten
full_name: Gutmann, Torsten
id: '118165'
last_name: Gutmann
- first_name: Rudolf
full_name: Pietschnig, Rudolf
last_name: Pietschnig
citation:
ama: Klintuch D, Höfler MV, Wissel T, Bruhn C, Gutmann T, Pietschnig R. Trifunctional
Silyl Groups as Anchoring Units in the Preparation of Luminescent Phosphole–Silica
Hybrids. Inorganic Chemistry. 2021;60(18):14263–14274. doi:10.1021/acs.inorgchem.1c01775
apa: Klintuch, D., Höfler, M. V., Wissel, T., Bruhn, C., Gutmann, T., & Pietschnig,
R. (2021). Trifunctional Silyl Groups as Anchoring Units in the Preparation of
Luminescent Phosphole–Silica Hybrids. Inorganic Chemistry, 60(18),
14263–14274. https://doi.org/10.1021/acs.inorgchem.1c01775
bibtex: '@article{Klintuch_Höfler_Wissel_Bruhn_Gutmann_Pietschnig_2021, title={Trifunctional
Silyl Groups as Anchoring Units in the Preparation of Luminescent Phosphole–Silica
Hybrids}, volume={60}, DOI={10.1021/acs.inorgchem.1c01775},
number={18}, journal={Inorganic Chemistry}, publisher={American Chemical Society},
author={Klintuch, Dieter and Höfler, Mark V. and Wissel, Till and Bruhn, Clemens
and Gutmann, Torsten and Pietschnig, Rudolf}, year={2021}, pages={14263–14274}
}'
chicago: 'Klintuch, Dieter, Mark V. Höfler, Till Wissel, Clemens Bruhn, Torsten
Gutmann, and Rudolf Pietschnig. “Trifunctional Silyl Groups as Anchoring Units
in the Preparation of Luminescent Phosphole–Silica Hybrids.” Inorganic Chemistry
60, no. 18 (2021): 14263–14274. https://doi.org/10.1021/acs.inorgchem.1c01775.'
ieee: 'D. Klintuch, M. V. Höfler, T. Wissel, C. Bruhn, T. Gutmann, and R. Pietschnig,
“Trifunctional Silyl Groups as Anchoring Units in the Preparation of Luminescent
Phosphole–Silica Hybrids,” Inorganic Chemistry, vol. 60, no. 18, pp. 14263–14274,
2021, doi: 10.1021/acs.inorgchem.1c01775.'
mla: Klintuch, Dieter, et al. “Trifunctional Silyl Groups as Anchoring Units in
the Preparation of Luminescent Phosphole–Silica Hybrids.” Inorganic Chemistry,
vol. 60, no. 18, American Chemical Society, 2021, pp. 14263–14274, doi:10.1021/acs.inorgchem.1c01775.
short: D. Klintuch, M.V. Höfler, T. Wissel, C. Bruhn, T. Gutmann, R. Pietschnig,
Inorganic Chemistry 60 (2021) 14263–14274.
date_created: 2026-02-07T15:47:54Z
date_updated: 2026-02-17T16:16:17Z
doi: 10.1021/acs.inorgchem.1c01775
extern: '1'
intvolume: ' 60'
issue: '18'
language:
- iso: eng
page: 14263–14274
publication: Inorganic Chemistry
publisher: American Chemical Society
status: public
title: Trifunctional Silyl Groups as Anchoring Units in the Preparation of Luminescent
Phosphole–Silica Hybrids
type: journal_article
user_id: '100715'
volume: 60
year: '2021'
...