The conformation conversion from achirality to chirality of a flexible alkane tetracarboxylate ligand in the metal-organic framework

By using the same meso ligand of 1,2,3,4-butanetetracarboxylic acid (H4BTCA), two plumbum coordination polymers have been synthesized, {[Pb(BTCA)0.5H2O]·H2O}n 1 and {[Pb(BTCA)0.5]}n 2. The conversion from achirality to chirality of BTCA4− was realized in compound 2 successfully, which provides an example for the conversion of organic compounds from achirality to chirality, although 2 is not a chiral compound. Hydrothermal method at higher temperature and the catalysis of NaOH play important roles in the successful conversion of BTCA4−.