Thiophene-2,5-dicarboxylic acid incorporated self-assembly of one-, two- and three-dimensional coordination polymers

Abstract

Six thiophene-2,5-dicarboxylic acid incorporated and self-assembled zinc(II), cobalt(II) and manganese(II) coordination polymers [Zn(Tda)(py)]_n (1), [Zn(Tda)(bipy)(H₂O)·1.5H₂O]_n (2), [Zn(Tda)(phen)(H₂O)]_n (3), [Co(Tda)(phen)(H₂O)]_n (4), [Mn(Tda)(phen)]_n (5) and [Mn(Tda)(H₂O)₂]_n (6) have been synthesised and structurally characterised. Complex 1 is characterised as a two-dimensional parallelogram with a cavity of about 10.4×10.4 Å, while complexes 2 and 3 (4) are one-dimensional linear and zig-zag coordination polymers with mainly hydrogen-bonding and stacking interactions contributing to their crystal packing, respectively. Complex 5 is a two-dimensional porous sheet with alternating 16- and 8-membered rings, while complex 6 is a three-dimensional porous coordination polymer. The diverse coordination properties of thiophene-2,5-dicarboxylate make it a good building block for the construction of coordination polymers of different architectures, which are dependent on both the end-capping ligand and the coordination geometry of the metal ions. Physical and thermal properties of these complexes have also been studied.