A couple of Co(II) enantiomers constructed from semirigid lactic acid derivatives

Abstract

Enantiopure organic linkers (R)-H2CBA and (S)-H2CBA have been synthesized from nature lactic acid and rigid 4-hydroxybenzoate. With the help of auxiliary ligand 4,4′-BIP, (R)-H2CBA and (S)-H2CBA afford two enantiomeric coordination polymers, namely [Co2((R)-CBA)2(4,4′-BIP)2]⋅xH2O (1-D) and [Co2((S)-CBA)2 (4,4′-BIP)2]⋅xH2O (1-L). In complexes 1-D and 1-L, the CBA2− ligands and dinuclear Co units form 4-connected Co-CBA layers, which are further linked to a pillared-layer framework with 2-fold interpenetration pcu structure by 4,4′-BIP ligands. Moreover, complex 1-D displays antiferromagnetic interactions.