SYNTHESIS AND STRUCTURE OF A BINUCLEAR [BIS(ETHANE-1,2-DIAMINE)NICKEL(II)]-MU-(ETHANE-1,2-DITHIOLATO)-[(ETHANE-1,2-DITHIOLATO)NICKEL(II)] COMPLEX [NI(EN)2(MU-C2O2S2)NI(C2O2S2)], AND THE RELATED 3,4-DIMERCAPTOCYCLOBUTENE-1,2-DIONATO COMPLEX

The reaction of planar bis nickel(II) chelates of the ethanebis(thioate) (dithiooxalate) dianion (C2O2S22-, dto) or the 3, 4-dimercaptocyclobutene-l, 2-dionate(2-) (dithiosquarate) dianion (C4O2S22-, dts) with bis(ethane-l, 2-diamine)nickel(n) dinitrate [NiII(en)2(NO3)2] leads to the formation of neutral binuclear complexes of the form [Ni(en)2Ni(L)2] (L = dto or dts), (1) and (2). An X-ray crystal structure of the dithiooxalate complex has been performed which confirms the formulation of a μ-dithiooxalato bridged binuclear complex based on analytical, magnetic and spectroscopic data. The crystals of [Ni(en)2Ni(dto)2] are orthorhombic, space group Penn a 8·371(8), b 17·65(1), c 23·37(2) Å and Z 8; a total of 853 unique data with I > 2σ(I) were refined to R 0·073. The molecule is found to be binuclear with a dithiooxalate dianion bridging a six-coordinate Ni(en)2O2 moiety and a planar four-coordinate Ni(dto)S2 group. © 1990 ASEG.