Synthesis and Structure of a Binuclear [Bis(ethane-1, 2-diamine)nickel(II)]- μ-(ethane-l, 2-dithiolato)-[(ethane-1, 2- dithiolato)nickel(II)] Complex [Ni(en)2(μ-C₂O₂S₂)Ni(C₂O₂S₂)]i and the Related 3, 4-Dimercaptocyclobutene- 1, 2-dionato Complex

The reaction of planar bis nickel(II) chelates of the ethanebis(thioate) (dithiooxalate) dianion (C₂O₂S₂^2-, dto) or the 3, 4-dimercaptocyclobutene-l, 2-dionate(2-) (dithiosquarate) dianion (C4O2S2^2-, dts) with bis(ethane-l, 2-diamine)nickel(n) dinitrate [Ni^II(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.