Syntheses and crystal structures of trimethyltin(IV) coordination polymers based on mixed ligands of 5-nitroisophthalate and 2,2′(4,4′)-bipy or phen

The trimethyltin(IV) polymer [(Me3Sn)2(nip) · EtOH]n (1) of 5-nitroisophthalic acid (H2nip) and its three derivatives with mixed organic N-donor ligands 2,2′-bipy [(Me3Sn)2(nip) · 2H2O] · [(Me3Sn)2(nip) · H2O] · 2(2,2′-bipy) (2) 4,4′-bipy {[(Me3Sn)2(nip)]2(4,4′-bipy)}n (3) or phen [(Me3Sn)2(nip) · H2O] · (phen) (4) have been synthesized by the reaction of trimethyltin(IV) chloride and H2nip when sodium ethoxide was added in the presence of 2,2′-bipy 4,4′-bipy or phen. All complexes 1–4 were characterized by elemental, IR, 1H, 13C, and 119Sn NMR spectroscopy and X-ray crystallography analyses. Crystal, data collection and structure refinement parameters for complexes 1, 2, 3 and 4 are shown in Table 1 and Table 2, respectively. The X-ray data showed the geometries of all the tin atoms in complexes 1–4 are trigonal bipyramidal. The X-ray analysis of 1 showed that the structure was a polymeric infinite chain with neighboring triorganotin centers being linked by dicarboxylate ligands and hydrogen bonds were found between adjacent chains. For 2, two different monomers were found, in one monomer, Me3Sn were coordinated to both carboxyl groups of the ligand and water molecules were coordinated to the two Sn(IV) centers. In the other monomer, water molecules were coordinated to only one Sn center. Co-crystallized2,2′-bipy was found in 2 and a 2D supermolecular structure was formed via O–H⋯O and O–H⋯N (N atoms derived from 2,2′-bipy) hydrogen bonds. In 3 however, a 2D polymeric block was formed due to the inversion center of the 4,4′-bipy. For 4, due to the O–H⋯O and O–H⋯N (N atoms derived from phen) hydrogen bonds and intermolecular Sn⋯O bonds, a 2D polymeric structure was formed.