Syntheses and 1D structures of organic–inorganic hydrid polymers combining M(ClO4)2 (M = Cd, Zn) junctions and the semi-flexible bis-pyridyl ligand 3-pmpmd (N,N′-bis(3-pyridylmethyl)pyromellitic diimide)

Two 1D organic–inorganic coordination polymers, [Cd(3-pmpmd)(CH3CN)2(H2O)2]n · 2n(ClO4)2 (1) and [Zn(3-pmpmd)1.5(H2O)2]n · 2n(ClO4)2 · nCH3CN (2), were obtained from M(ClO4)2 (M = Cd, Zn) and the semi-flexible 3,3′-N-donor bis-pyridyl ligand 3-pmpmd: 1 has an 1D zigzag framework with 3-pmpmd in the ZT-mode (anti, trans-) conformation, while 2 has an 1D rod and loop network with 3-pmpmd in both ZT- and ZC-mode (anti, cis-) conformations. Results showed that the metal ions could influence the coordination mode of a semi-flexible bis-pyridyl ligand.