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11.
Dionisia Sanz Rosa M. Claramunt Ibon Alkorta Goar Sánchez‐Sanz José Elguero 《Magnetic resonance in chemistry : MRC》2012,50(3):246-255
The structure of glibenclamide, 5‐chloro‐N‐(2‐{4‐[(cyclohexylamino)carbonyl] aminosulfonyl}phenyl) ethyl)‐2‐methoxybenzamide, an important antidiabetic drug, has been studied both in solution and in the solid state by a combination of NMR spectroscopy and theoretical calculations. The possibility that glibenclamide suffers a tautomerization under melting to afford a desmotrope was rejected. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
12.
A theoretical and experimental study of the NMR spectra of 4,5,6,7‐tetrafluorobenzazoles with special stress on PCM calculations of chemical shifts
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Ibon Alkorta José Elguero Marta Pérez‐Torralba Concepción López Rosa M. Claramunt 《Magnetic resonance in chemistry : MRC》2015,53(5):353-362
The chemical shifts and several 19F–19F, 13C–19F and 1H–19F spin‐spin coupling constants (SSCSs) of eight 4,5,6,7‐tetraflurobenzazoles (three benzimidazoles, three benzimidazolinones and two indazoles) have been determined. The chemical shifts were discussed using gauge including atomic orbital‐density functional theory calculations taking into account solvent effects (polarizable continuum model) and, for the solid state, hydrogen bonds (clusters up to three molecules). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
13.
Rosa M. Claramunt Pilar Cornago M. Dolores Santa María Verónica Torres Elena Pinilla M. Rosario Torres 《Supramolecular chemistry》2013,25(4):349-356
The X-ray structure and the solid-state NMR measurements, mainly 15N CPMAS of the labelled compound, allow to determine the static and dynamic properties of 3(5)-ethyl-5(3)-phenyl-1H-pyrazole. The compound is a tetramer formed by three 5-ethyl-3-phenyl-1H-pyrazole and one 3-ethyl-5-phenyl-1H-pyrazole tautomers in dynamic equilibrium with the complementary situation. 相似文献
14.
Dionisia Sanz Rosa M. Claramunt François Mathey Ibon Alkorta Goar Sánchez-Sanz José Elguero 《Comptes Rendus Chimie》2013,16(10):937-944
This paper reports the study by NMR spectroscopy and ab initio methods of the structure of 3,4-dimethyl-1-cyanophosphole and its dimer. The dimer presents a P···P interaction of the pnictogen type due to the presence of σ-holes. NMR of the monomer was recorded in CDCl3 solution while NMR of the dimer corresponds to the solid state (CPMAS) experiments. The 2pJPP spin–spin coupling constant has not been measured, but calculated at the B3LYP level. AIM, NBO and ELF methodologies have been used to describe the electronic structure of the dimer. 相似文献
15.
The properties of 28 molecules together with 12 transition states belonging to the series of azido-azines, tetrazolo-azines, diazo-azines, and 1,2,3-triazolo-azines have been studied at the B3LYP/6-31G(d), B3LYP/6-311++G(d,p) and, for 26 cases, at the G3B3 level. Energies, NICS and bond critical points were used to discuss the ring-chain tautomerism of these compounds in relation with the aromaticity of the azines (pyridine, pyrimidine, quinazoline, 1,3-diazapyrene, and perimidine) and the azoles (tetrazoles and 1,2,3-triazoles). 相似文献
16.
17.
Christelle Vangenot Christophe Claramunt 《International Journal of Infrared and Millimeter Waves》1994,15(8):1361
First announcement the 20th annual international conference on infrared and millimeter waves 相似文献
18.
María DS Farrán MÁ García MÁ Pinilla E Torres MR Elguero J Claramunt RM 《The Journal of organic chemistry》2011,76(16):6780-6788
Four hosts (7-10) containing 2,6-bisamidopyridine- and 2,5-bisamidopyrrole-bearing pyridyl or 1,8-naphthyridyl groups have been prepared and their structures studied by a combination of multinuclear NMR spectroscopy and X-ray crystallography. Their behavior in molecular recognition of urea derivatives, including (+)-biotin methyl ester, has been approached by molecular modeling (Monte Carlo conformational search, AMBER force field). The minimum energy values for the complexes are correlated with the experimental binding energies determined by means of (1)H NMR titrations. 相似文献
19.
The synthesis and properties of rhodium(I) complexes of formulae [“RhCl(diolefin)”2(L)] (or [Rh(Cl(diolefin)(L)]), and [Rh(diolefin)(L)]n(ClO4)n are reported. These complexes react with carbon monoxide to yield the related carbonyl derivatives. Ligands used were pyridazine, 4,6-dimethyl-pyrimidine, 4,6-bis(3,5-dimethylpyrazol-1-yl)pyrimidine, 3,6-bis(3,5-dimethylpyrazol-1-yl)pyridazine and 3-(3,5-dimethyl-pyrazol-1-yl)-6-chloropyridazine. Related iridium(I) and gold(I) compounds are also reported. 相似文献
20.
Sanz D Claramunt RM Singh SP Kumar V Aggarwal R Elguero J Alkorta I 《Magnetic resonance in chemistry : MRC》2005,43(12):1040-1043
The combined use of 1H NMR spectroscopy with theoretical calculations of chemical shifts (GIAO) and coupling constants (B3LYP/6-311 ++G**) of a 5-hydroxy-5-trifluoromethyl-Delta2-isoxazoline has enabled solving the problem of the assignments of the diastereotopic protons in this compound. This result has been extended to 5-hydroxy-5-trifluoromethyl-Delta2-pyrazolines and the corresponding 5-trichloromethyl derivatives. 相似文献