Separation of isomers of chiral thiourea derivatives via spontaneous resolution and rationale of molecular recognition†‡

Abstract

Enrichment of enantiomers during crystallization of racemic thiourea derivatives was investigated. The spontaneous resolution of a chiral thiourea derivative via preferential crystallization is attributed to thermodynamic stability when molecules of identical chirality bind with each other in the crystal lattice. Single crystal X-ray analysis reveals the interactions responsible for self-recognition of molecules of the same chirality in the unit cell. The tendency of the thiourea derivative to form a conglomerate is supported by IR spectroscopy, thermal analysis and computational studies.