THE SYNTHESIS AND CRYSTAL-STRUCTURE OF ETHYLENEDINITRILOTETRAACETAMIDOXIME NICKEL(II) SULFATE TRIHYDRATE

The synthesis of the first reported complex formed between a transition metal ion and the potentially hexadentate ligand, ethylenedinitrilotetraacetamidoxime (EDTAO), is presented. The crystal structure of a nickel(II) complex with EDTAO, C10H24N10O4, has been determined. The intensities of 2183 reflections (2030 observed) for [Ni(EDTAO)]SO4.3H(2)O were collected by diffractometer methods using Cu K alpha radiation. The space group is P2(1)2(1)2(1) (No. 19). Cell dimensions are a = 11.407(2), b=11.820(2), c=15.937(2) Angstrom and alpha=beta=gamma=90 degrees with 4 molecules in the unit cell. The observed density is 1.710 g cm(-3) Refinement was by full-matrix least-squares methods to a conventional R value of 0.025. The complex consists of discrete Ni(EDTAO)(2+) cations and sulfate anions; the cation existing as a distorted octahedral complex with bonding through to amine and four oxime nitrogen atoms. Neither the sulfate nor the water molecules are involved in the coordination. The Ni-N(amine) distances are 2.123(2) and 2.134(2) Angstrom, while the Ni-N(oxime) distances are 2.099(2), 2.074(2), 2.078(2) and 2.077(2) Angstrom.