Homochiral crystallization of single-stranded helical coordination polymers: generated by the structure of auxiliary ligands or spontaneous symmetry breaking

Homochiral crystallizations of single-stranded helical coordination polymers were constructed using the V-shaped bridging ligand dicyanamide (mu(1,5)-dca(-)) and chelate auxiliary ligands. The enantiomeric nature of 1 and 2 is directly induced by the chirality of the auxiliary ligands. Whereas, the homochirality feature for 3 stems from the spontaneous symmetry breaking in crystallization.