Chromone studies. Part 3. NMR analysis of rotational isomerism in 4-oxo-4H-chromene-2-carboxamides
Abstract
Temperature dependent splitting of N-alkyl 1H and 13C NMR signals in a series of 4-oxo-4H-chromene-2-carboxamides has been analysed in terms of rotation of the amide group. Rotational barriers have been calculated from dynamic 1H NMR data and the conformational options have been explored.