Crystal engineering based on preferred mirror image recognition in square planar Pd(ii) complexes

Abstract

Structurally related palladium complexes of opposite chirality have been prepared and successfully used as building blocks for the crystal engineering of well-ordered solids in non-centrosymmetric space groups. In agreement with the idea of quasiracemic design, these target compounds mimic the structure of a racemate and crystallize in space group C2 with a pair of heterochirally similar molecules in the asymmetric unit. One of the racemic parent structures adopts a very similar packing, crystallizing in the centrosymmetric supergroup C2/c. In addition to the binary crystals and the racemate, solid solutions of homochirally similar molecules have been studied: they are isomorphous with the enantiomerically pure constituents.