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13C-NMR ano theoretical stuoies of internal rotation in methylateo anillnes
(Socieda Chilena de Quìmica, 1997-08-01)
The conformational properties of ten ring-methylated N-methyl- and N,Ndimethylanilines
have been studied using 13C-NMR chemical shifts and spin-Iattice
relaxation times in CDCI3, and semi-empírical (AM1) quantum-chemical ...
Spectral study of carbon-13 N.M.R. of three Parkia gums
(Facultad Experimental de Ciencias de la Universidad del Zulia, 2014)
A Multi-standard Approach for GIAO 13C NMR Calculations
(American Chemical Society, 2009-12)
The influence of the reference standard employed in the calculation of 13C NMR chemical shifts was investigated over a large variety of known organic compounds, using different quantum chemistrymethods and basis sets. After ...
Use of long-range C-H ((n)J n > 3) heteronuclear multiple bond connectivity in the assignment of the C-13 NMR spectra of complex organic molecules
(BENTHAM SCIENCE PUBL LTD, 2001-03)
The structural elucidation of complex organic molecules relies heavily on the application of proton detected heteronuclear NMR. Among these techniques, the HMBC NMR experiment is probably the most useful 2D NMR method The ...
13C-NMR and theoretical studies of internal rotation in methylated anilines
(1998)
The conformational properties of ten ring-methylated N-methyl- and N,N-dimethylanilines have been studied using 13C-NMR chemical shifts and spin-lattice relaxation times in CDCl3, and semi-empirical (AM1) quantum-chemical ...
Automatic identification by C-13 NMR of substituent groups bonded in natural product skeletons
(Elsevier B.V., 2002-11-01)
The aim of this paper is to present a procedure that utilizes C-13 NMR for identification of substituent groups which are bonded to carbon skeletons of natural products. For so much was developed a new version of the program ...
Structural characterization of strained oxacycles by 13C NMR spectroscopy
(Arkat USA, 2011-02)
The 1H and 13C NMR data of a series of epoxy-and epidioxy-bridged tetrahydropyran derivatives containing the same basic carbon skeleton, are reported. 13C NMR spectroscopy was shown to be useful for structural determination ...
Principal component analysis in studies of substituent-induced carbon-13 chemical shifts of halogenated aliphatic compounds
(Elsevier Science BvAmsterdamHolanda, 2004)
Intramolecular interactions in alpha-mono-substituted acetic acids through C-13 NMR chemical shifts and theoretical calculations
(Canadian Soc Analytical Sciences & SpectroscopyOttawaCanadá, 2000)
13C-NMR spectroscopy of para-substituted benzylideneacetones. I. Long distance electronic effects
(Marcel Dekker Inc., 1997)
Para-benzylideneacetones present a characteristic long distance charge transfer pattern, where the olefinic bridge (CH=CH) and the aromatic ring (Ph) carbon centers are perturbed according to the nature of the para-substituent ...