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

Abstract

The reaction of planar bis nickel(II) chelates of the ethanebis ( thioate ) ( dithiooxalate ) dianion (C2O2S22-, dto ) or the 3,4-dimercaptocyclobutene-1,2-dionate(2-)( dithiosquarate ) dianion (C4O2S22-, dts ) with bis (ethane-1,2-diamine)nickel(II) 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 Pcnn a 8.371(8), b 17.65(1), c 23.37(2)Ǻ 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.