Anisatin: a Crystallographic, N.M.R. and Theoretical Conformation Study

Abstract

The convulsant compound anisatin has been studied by ¹H n.m.r ., and X- ray crystallography, to establish its molecular geometry. The n.m.r . measurements included an analysis of proton-proton vicinal coupling constants and saturation transfer experiments which monitored exchange of the hydroxy groups of anisatin. The former analysis was used to obtain a solution conformation via the Karplus equation while the latter experiments yield information on intramolecular hydrogen bonding. The experimental geometry is compared to that obtained by several theoretical methods, including MINDO/3, MNDO, AM1 and MM2. The AM1 optimized geometry was closest to that of the crystal structure.