Transfer of 2-Aminoethanethiolate (aet) from Nickel(II) to Cobalt(III) Coordination Sphere. Synthesis, Crystal Structure, and Some Properties of an S-Bridged Trinuclear Complex [Ni{Co(aet)2(en)}2]4+

Abstract

Abstract The reaction of [CoCl2(en)2]+ with [Ni(aet)2] in water gave an S-bridged CoIIINiIICoIII trinuclear complex, [Ni{Co(aet)2(en)}2]4+ (1), which indicates that the bidentate-N,S ligand aet transfers from the NiII to the CoIII coordination sphere. 1 formed only the racemic compound of Δ(C2-cis(S))Δ(C2-cis(S)) and Λ(C2-cis(S))Λ(C2-cis(S)) isomers, and its crystal structure was analyzed by X-ray diffraction. [Ni{Co(aet)2(en)}2]Cl4·6H2O, chemical formula C12H52N8O6S4Cl4Co2Ni, crystallizes in the monoclinic space group C2/c with a = 14.987(4), b = 19.480(3), c = 12.916(4) Å, β = 113.67(1)°, V = 3454(1) Å3, Z = 4, and R = 0.046. The central NiII atom is situated in an environment markedly distorted from a square-planar to a tetrahedral geometry, coordinated by four thiolato sulfur atoms from two octahedral C2-cis(S)-[Co(aet)2(en)]+ units. The H2O2 oxidation of 1 caused the cleavage of the Ni–S bonds to afford the mononuclear sulfinato complex, [Co(NH2CH2CH2SO2-N,S)2(en)]+ (2), retaining the C2-cis(S) geometry of 1. 1 and 2 were optically resolved and their absorption, CD, and NMR spectral behavior are reported.