Coordination Polymers of Zinc with (η6-Benzenecarboxylate) Chromium Tricarbonyl

Different coordination polymers were obtained by the reaction of (benzoic acid) chromium tricarbonyl with zinc acetate in the presence of various organic dipyridyl linkers. Depending on the nature of the linker either monomeric or polymeric compounds were obtained. Reactions of (benzoic acid) chromium tricarbonyl with zinc acetate and bidentate pyridine based ligands 4,4′-bipyridine (4,4′-bipy), 1,2-bis(4-pyridyl)ethane (bpe), 1,3-bis(4-pyridyl)propane (tmdp), and 2,2′dipyridylamine (DPA) afforded the novel coordination polymers [Zn[{η6-C6H5COO}Cr(CO)3]2(4,4′-bipy)]n, [Zn[{η6-C6H5COO}Cr(CO)3]2(bpe)]n, [Zn[{η6-C6H5COO}Cr(CO)3]2(tmdp)}]n, and the monomeric complex [Zn[{η6-C6H5COO}Cr(CO)3]2(DPA)]. The solid state structures of all compounds were determined by single crystal X-ray diffraction. By using 1,3-bis(4-pyridyl)propane as a linker a chiral infinite helical structure was formed in the solid state. Thermogravimetric analysis (TGA) studies showed that upon heating the carbonyl groups of the {η6-C6H5COO}Cr(CO)3 anion were lost before the organic ligand sphere was thermally decomposed.