A new optical resolution method: coordinative resolution of mandelic acid esters. The crystal structure of calcium hydrogen (2R,3R)-O,O′-dibenzoyl tartrate–2(R)-(–)-methyl mandelate
Abstract
A new and efficient resolution, based on the finding that the calcium acid salt of O,O′-dibenzoyltartaric acid forms crystalline coordination complexes with enantiomers of α-hydroxy acid esters, is reported.