SYNTHESIS AND CHARACTERIZATION OF (MU-OXALATO) NICKEL(II) COMPLEXES

Three new nickel(II) dinuclear oxalato-bridged compounds Ni(TAA)(ClO4) . 0.5ox (1), Ni-2(APO-sal(2))ox . 2H(2)O (2) and Niphen(2)oxNiacac(2) . 4H(2)O (3) have been characterized [TAA = N(CH2CH2NH2)(3) ox = oxala te, phen = 1,10-phenanthroline, acac = acetylacetonate and APO-sal(2) is the Schiff base formed by the condensation of salicylaldehyde and 1 ,3-diamino-2-propanol]. The crystal structure of 1 has been deter mine d by a single-crystal X-ray analysis. The nickel atom is coordinated b y two oxygen atoms of an oxalato ligand and four nitrogen atoms belong ing to TAA in an octahedral arrangement. The intermetallic distance of Ni(1)-Ni(2) is 5.412(1) Angstrom. Magnetic measurements (77-300 K) sh ow that three compounds are antiferromagnetically coupled, J = -14.4, -11.25 and -19.3 cm(-1) for 1, 2 and 3, respectively. Copyright (C) 19 97 Elsevier Science Ltd.