Probing the mobility of ibuprofen confined in MCM-41 materials using MAS-PFG NMR and hyperpolarised-129Xe NMR spectroscopy

The pressure dependence of the 129Xe chemical shift tensor confined in the Tris(o-phenylenedioxy) cyclotriphosphazene (TPP) nanochannel was investigated by high-pressure 129Xe NMR spectroscopy. The observed 129Xe spectrum in the one-dimensional TPP nanochannel (0.45 nm in diameter) exhibits a powder pattern broadened by an axially symmetric chemical shift tensor. As the pressure increases from 0.02 to 7.0 MPa, a deshielding of 90 ppm is observed for the perpendicularcomponent of the chemical shift tensor δ⊥, whereas a deshielding of about 30 ppm is observed for the parallel one, δ‖. This suggests that the components of the chemical shift tensor, δ‖ and δ⊥, are mainly dominated by the Xe-wall and Xe-Xe interaction, respectively. Furthermore, the effect of helium, which is present along with xenon gas, on the 129Xe chemical shift is examined in detail. The average distance between the Xe atoms in the nanochannel is estimated to be 0.54 nm. This was found by using δ⊥ at the saturated pressure of xenon, and comparing the increment of the chemicalshift value in δ⊥ to that of a β -phenol/Xe compound.

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Ion Transport Properties and Ionicity of 1,3-Dimethyl-1,2,3-Triazolium Salts with Fluorinated Anions

Materials ◽

10.3390/ma11091723 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1723 ◽

Cited By ~ 3

Author(s):

Martin Pulst ◽

Yury Golitsyn ◽

Detlef Reichert ◽

Jörg Kressler

Keyword(s):

Nuclear Magnetic Resonance ◽

Nmr Spectroscopy ◽

Diffusion Coefficients ◽

Important Class ◽

Spectroscopy Data ◽

Ion Conductivities ◽

Electrochemical Devices ◽

Pfg Nmr ◽

Conductive Properties ◽

Triazolium Salts

1,2,3-Triazolium salts are an important class of materials with a plethora of sophisticated applications. A series of three novel 1,3-dimethyl-1,2,3-triazolium salts with fluorine, containing anions of various size, is synthesized by methylation of 1,2,3-triazole. Their ion conductivity is measured by impedance spectroscopy, and the corresponding ionicities are determined by diffusion coefficients obtained from 1H and 19F pulsed field gradient nuclear magnetic resonance (PFG NMR) spectroscopy data, revealing that the anion strongly influences their ion conductive properties. Since the molar ion conductivities and ionicities of the 1,3-dimethyl-1,2,3-triazolium salts are enhanced in comparison to other 1,2,3-triazolium salts with longer alkyl substituents, they are promising candidates for applications as electrolytes in electrochemical devices.

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ChemInform Abstract: Characterization of NiNa-Y Zeolite by 129Xe NMR Spectroscopy.

Chemischer Informationsdienst ◽

10.1002/chin.198618017 ◽

1986 ◽

Vol 17 (18) ◽

Author(s):

E. W. SCHARPF ◽

R. W. CRECELY ◽

B. C. GATES ◽

C. DYBOWSKI

Keyword(s):

Nmr Spectroscopy ◽

Y Zeolite ◽

Abstract Characterization ◽

129Xe Nmr

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ChemInform Abstract: Formation and Growth of a Ru Cluster in a Y Zeolite Supercage Probed by 129Xe NMR Spectroscopy and Xenon Adsorption Measurements.

ChemInform ◽

10.1002/chin.199309268 ◽

2010 ◽

Vol 24 (9) ◽

pp. no-no

Author(s):

S. J. CHO ◽

S. M. JUNG ◽

Y. G. SHUL ◽

R. RYOO

Keyword(s):

Nmr Spectroscopy ◽

Y Zeolite ◽

129Xe Nmr ◽

Xenon Adsorption

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Hoveyda–Grubbs type metathesis catalyst immobilized on mesoporous molecular sieves MCM-41 and SBA-15

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.7.4 ◽

2011 ◽

Vol 7 ◽

pp. 22-28 ◽

Cited By ~ 27

Author(s):

Hynek Balcar ◽

Tushar Shinde ◽

Naděžda Žilková ◽

Zdeněk Bastl

Keyword(s):

Nmr Spectroscopy ◽

Molecular Sieves ◽

Direct Interaction ◽

Mesoporous Molecular Sieves ◽

Support Surface ◽

Wall Surface ◽

Ring Closing Metathesis ◽

Immobilized Catalysts ◽

Metathesis Catalyst ◽

Mcm 41

A commercially available Hoveyda–Grubbs type catalyst (RC303 Zhannan Pharma) was immobilized on mesoporous molecular sieves MCM-41 and on SBA-15 by direct interaction with the sieve wall surface. The immobilized catalysts exhibited high activity and nearly 100% selectivity in several types of alkene metathesis reactions. Ru leaching was found to depend on the substrate and solvent used (the lowest leaching was found for ring-closing metathesis of 1,7-octadiene in cyclohexane – 0.04% of catalyst Ru content). Results of XPS, UV–vis and NMR spectroscopy showed that at least 76% of the Ru content was bound to the support surface non-covalently and could be removed from the catalyst by washing with THF.

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