Bulletin of the Chemical Society of Japan

Restricted Rotation in Aromatic Ketones. I. Substituent Effects on the Barrier to Rotation about the Benzene-to-Carbonyl Bond

N Nakamura, M Oki

Index: Nakamura,N.; Oki,M. Bulletin of the Chemical Society of Japan, 1972 , vol. 45, p. 2565 - 2570

Full Text: HTML

Citation Number: 8

Abstract

Several aryl isopropyl ketones and aryl benzyl ketones were synthesized and their NMR spectra were recorded at various temperatures. Their temperature dependence was accounted for in terms of the restricted rotation about the benzene-to-carbonyl bond, whose free energies of activation at the coalescence temperatures varied from 9 to 15 kcal/mol according to the steric effect of ortho substituents, the buttressing effect of meta ...