Synthesis and Crystal Structure of a New Mononuclear Cobalt(Ⅲ) Complex with 2,2′-Dipyridylamine and Glycine as Ligands

A new mononuclear cobalt(III) complex [Co(dpa)2(Gly)](ClO4)2′4H2O was synthesized by the reaction of Co2+, glycine (gly) and 2,2′-dipyridylamine (dpa) in a methanol-water solution, and its structure was characterized by IR, EA, ES-MS and X-ray structure analysis. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.8795(2), b = 13.2904(2), c = 19.1104(2) , β = 109.378(1)°, V = 3085.89(8) 3, Z = 4, Mr = 746.36, Dc = 1.606 g/cm3, μ = 0.808 mm-1, F(000) = 1536, the final R = 0.0543 and wR = 0.1306 for 5393 independent reflections. The magnetic measurement of the compound at room temperature shows that it is diamagnetic and the cobalt ion is in low spin +3 oxidation state. ES-MS experiments show that the [Co(dpa)2(Gly)]2+ cation is very stable in the methanol solution.