A tris(thioxanthate) of nickel(II) and its transformation to a dinuclear trithiocarbonate complex. Synthesis and structure of [Et4N]2[Ni2(SEt)2(CS3)2] (original) (raw)

1992, Inorganic Chemistry

The tris(thioxanthate)nickel(II) salt [Et4N] [Ni(t~n)~] has been synthesized. The S,-coordinated bivalent metal center (2.97 ps) is oxidizable, the El,, of the Ni"'(txn),-NilI(txn); couple being 0.09 V vs SCE (CH2C12, 253 K). The frozen-solution (77 K) EPR spectrum of electrogenerated Ni(txn), is compatible with the d$ ground state (g,,, 2.083; g, components, 2.122 and 2.146). At ambient temperature Ni(txn)< undergoes a facile spontaneous decomposition, affording the dimeric complex Ni2(SEt),(CS3)?-. A rationale for this transformation is proposed. The structure of [Et4N],[Ni,(SEt),(CS,),1 is reported: a = 31.279 (9) A, b = 13.670 (5) A, c = 16.900 (4) A, 6 = 102.63 (2)', V = 7050 (4) A', R = 0.0733, R, = 0.0720, space group C2/c, and Z = 8. In the dimeric anion, the metal atoms are thiolato bridged and one CS3,-ligand is chelated to each metal center. The average Ni-S(che1ate) and Ni-S(bridge) lengths are 2.173 (6) and 2.189 (5) A, respectively; the Ni-Ni contact (d) is 2.767 (3) A. The dihedral angle (a) between the two edge-sharing NiS, planes is 11 1.1 (2)O. In a group of complexes having this structural feature, d correlates linearly with sin (4 2) .