Conformational analysis of acyclic compounds with oxygen–sulphur interactions. Some 2-thio-derivatives of 1-phenylethanol

Abstract

A conformational study of 1-phenyl-2-X-ethanol [X = SH, SCH₃, SOCH₃, SO₂CH₃, and S(CH₃)₂] is reported. The values of the vicinal and long-range (H–O–C–C–H and H–C–S–C–H) coupling constants obtained from n.m.r. spectra recorded in several solvents indicate that in most cases only one of the possible conformations around the C–C bond is preferred. This conformation, in which the sulphur function has a gauche-relationship with the hydroxy-group and an anti-relationship with the phenyl group, is probably stabilized more by polar interactions between the heteroatoms than by other factors.