A LINEAR MIXED OXIDATION-STATE TRINUCLEAR COBALT COMPLEX WITH 6 BRIDGING SULFITO LIGANDS

A linear mixed oxidation state trinuclear cobalt complex {Co(II)[O3S)3Co(III)(NH3)3]2}4- (1), having six bridging sulfito ligands, was obtained by the reaction between Na2S2O4 and an oxidized solution of CoCl2 in ammonia. The structure of 1, as found in the crystals of [(NH3)5CoSO3]4.1.16H2O, was determined by X-ray crystallography. The compound is triclinic, space group P1BAR with a = 11.956(2), b = 13.260(3), c = 11.480(2) angstrom, alpha = 96.50(3), beta = 111.86(3), gamma = 81.61(3)-degrees, V = 1668(1) angstrom and Z = 1. Complex 1 can be regarded as two tridentate [(NH3)3Co(SO3)3]3- ligands, oxo coordinated to a Co2+ ion, forming an octahedral geometry. The dimensions of 1 correspond closely to full D3d symmetry.