The alpha-substituent effect of alkyl groups in the C-13 NMR and IR data of some aliphatic nitriles

dc.creatorRittner, R
dc.creatorTormena, CF
dc.creatorCarniero, PIB
dc.date2002
dc.date2014-08-01T18:23:59Z
dc.date2015-11-26T17:01:27Z
dc.date2014-08-01T18:23:59Z
dc.date2015-11-26T17:01:27Z
dc.date.accessioned2018-03-28T23:49:16Z
dc.date.available2018-03-28T23:49:16Z
dc.identifierCanadian Journal Of Analytical Sciences And Spectroscopy. Spectroscopy Soc Canada, Ottawa, v. 47, n. 1, n. 29, n. 35, 2002.
dc.identifier1205-6685
dc.identifierWOS:000178351000004
dc.identifierhttp://www.repositorio.unicamp.br/jspui/handle/REPOSIP/78303
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/78303
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1278722
dc.descriptionCarbon-13 NMR spectra of some aliphatic nitriles, from acetonitrile to octanonitrile, were recorded, and unequivocal assignments of the chemical shifts through the use of HSQC and gHMBC sequences were performed. Cyano group stretching frequencies (nu(CN)), C-13 NMR chemical shifts for the CN and alpha-CH2 carbon atoms were correlated with electronic and steric parameters and also with calculated charge densities. No correlation between NMR and IR values was observed. However, it was observed a decrease of nu(CN) with the increase in the substituent polarizability. Opposite tendencies were observed for the delta(CN) and delta(alpha-CH2) values. delta(alpha-CH2) increases with the increase in substituent steric effect and with the decrease of calculated charge densities. A reasonable agreement between the methylene and methyl carbon experimental and theoretically calculated (HF) chemical shifts is observed, and also for the cyano carbon when MP2 or B3LYP methods were used. The unique properties of the ethyl group drive the delta(CN), delta(alpha-CH2) I and nu(CN) to apparently unexpected values, which. 2 is noted in all linear and non-linear correlations here presented, and may be due to the absence of a carbon atom in the gamma-position in relation to the CN or to the alpha-CH2 group.
dc.description47
dc.description1
dc.description29
dc.description35
dc.languageen
dc.publisherSpectroscopy Soc Canada, Ottawa
dc.publisherOttawa
dc.publisherCanadá
dc.relationCanadian Journal Of Analytical Sciences And Spectroscopy
dc.relationCan. J. Anal. Sci. Spectrosc.
dc.rightsfechado
dc.sourceWeb of Science
dc.subjectaliphatic nitriles
dc.subjectsubstituent effects
dc.subjectcarbon-13 NMR
dc.subjectinfrared spectra
dc.subjecttheoretical calculation
dc.subjectChemical-shifts
dc.subjectResonance
dc.subjectSpectra
dc.subjectAcids
dc.titleThe alpha-substituent effect of alkyl groups in the C-13 NMR and IR data of some aliphatic nitriles
dc.typeArtículos de revistas


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