The varied structures of cobalt(II)-pyridine (py)-sulfate: [Co(SO4)(py)4] n , [Co2(SO4)2(py)6] n , and [Co3(SO4)3(py)11] n

3,5-Lutidine penta-aqua sulfate complexes of first-row transition metals: [M(3,5-lutidine)(H2O)5]SO4, with M = Mn, Co, Ni, and Zn

The reactions of MnSO4·H2O, CoSO4·7H2O, NiSO4·6H2O and ZnSO4·7H2O with 3,5-lutidine (3,5-di-methyl-pyridine) yield crystals of penta-aqua-(3,5-di-methyl-pyridine-κN)manganese(II) sulfate, [Mn(C7H9N)(H2O)5]SO4, (1), penta-aqua-(3,5-di-methyl-pyridine-κN)cobalt(II) sulfate, [Co(C7H9N)(H2O)5]SO4, (2), penta-aqua-(3,5-di-methyl-pyridine-κN)nickel(II) sulfate, [Ni(C7H9N)(H2O)5]SO4, (3), and penta-aqua-(3,5-di-methyl-pyridine-κN)zinc(II) sulfate, [Zn(C7H9N)(H2O)5]SO4, (4), which were characterized by single-crystal X-ray diffraction. The four crystals are isostructural, demonstrating near identical unit-cell parameters and atomic positions. The metal atoms are all octa-hedrally coordinated, with one lutidine ligand and five water ligands. The sulfate dianion hydrogen bonds with the coordinated water mol-ecules of the dicationic metal complex salts, generating infinite three-dimensional networks.

A cuboidal [Cu4(SO4)4] structure supported by β-picoline ligands

The solid-state structure of the cobalt-β-picoline-sulfate complex tetra-μ3-sulfato-tetra-kis-[bis-(3-methyl-pyridine)-cobalt(II)], [Co4(SO4)4(C6H7N)8], is reported. The tetra-meric cobalt cluster contains a cuboidal core comprised of four cobalt(II) cations and four sulfate anions at alternate cube vertices. The cobalt corners are each capped with two β-picoline ligands. The sulfate anions adopt a rare [3.2110] bridging motif, and the cuboidal cluster is unprecedented in coordination chemistry.