Effects of p-substituents on the conformation of acetophenone

Abstract

Experimental dipole moments and infinite-dilution molar Kerr constants are reported for six p-substituted acetophenones (CH3COC6H4X; X = Me, But, NO2, CN, F, Br) as solutes in carbon tetrachloride at 298 K. Analysis of these results and reconsideration of previously reported data for acetophenone and p-chloroacetophenone yields the dihedral angle, Φ, between the planes of the carbonyl and aryl groups in the effective conformation of each molecule (X = H, Φ = 0°; Me, 0°; But, 10�10°; NO2, 20�15°; NO2, 20�20°; F, 27�5°; Cl, 32�5°; Br, 30�10°).