(S)-(2,2-Dimethyl-5-oxo-1,3-dioxolan-4-yl)acetic acid

Abstract

The title compound, C7H10O5, was obtained from the reaction of (S)‐malic acid and 2,2‐dimethoxypropane using p‐TsOH as acid catalyst. The molecule is enantiomerically pure, as determined from optical rotation. The dioxolanone ring is a slightly distorted plane with the methylenecarboxy group equatorial. The carboxy group is syn to the face of the ring and anti to the ring H atom. Molecules are linked by O—H...O hydrogen bonds between the hydroxy group of the carboxyl group and the dioxolane carbonyl O atom, generating helices parallel to b. Only the S enantiomer is present in the crystal structure, which is consistent with the starting material and its synthetic sequence.