ISSN:
0749-1581
Keywords:
Schiff bases
;
Tautomerism
;
13C NMR CP/MAS
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
13C and 1H NMR spectra of six Schiff bases formed from 2-hydroxy-1-naphthaldehyde and substituted anilines were measured and assigned in a variety of solvents. Based on the 13C chemical shifts and 3J(CH,NH), the ratio of the keto-amine and phenol-imine tautomers was derived using both 13C chemical shifts and 1H-1H coupling constants, the two methods giving comparable results. The solid-state 13C NMR spectra of two of these Schiff bases were also measured and interpreted. Based on chemical shift assignments from solution NMR, which showed a relationship between certain shifts and the proportions of the tautomers, it has been shown that these compounds exist essentially as the keto-amine form in the solid, the tautomer previously shown to be the more thermodynamically stable.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260311107
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