Nonempirical calculations of NMR indirect spin-spin coupling constants. Part 14: azomethines of the alpha, beta-unsaturated aldehydes

Magn Reson Chem. 2006 Feb;44(2):178-87. doi: 10.1002/mrc.1748.

Abstract

Configurational assignment of seven azomethines obtained from the alpha-functionally substituted and nonsubstituted alpha,beta-unsaturated aldehydes has been performed on the basis of experimental measurements and the high-level ab initio calculations of their 1J(C,C) and 1J(C,H), involving the alpha-imino carbon that demonstrated the marked stereochemical dependence of both coupling constants upon the orientation of the nitrogen lone pair in the diverse isomers of the title azomethines.