On the gearing of methyl groups in hexamethylbenzene

Abstract

Abstract Empirical force field calculations were performed on hexamethylbenzene to elucidate the internal motions of the methyl groups. When the benzene ring is constrained to be planar (as in solid‐phase studies), the methyl groups undergo a geared, disrotatory motion. When this constraint is relaxed, results are force field dependent. Calculated barriers are in good agreement with experimentally determined values.