SYNTHESIS AND CHARACTERIZATION OF COMPLEXES OF MN(II) WITH 3,6-DICARBOXYPYRIDAZINE

Complexation of the diacid ligand 3,6-dicarboxypyridazine(H2DCP) in an acid environment with manganese (II) salt leads to formation of a mon onuclear complex [Mn(HDCP)(2)(H2O)(2)] 2H(2)O with a ratio Mn (II)/lig and of 1:2. The Mn (II) ion is six coordinate, with high spin. The eff ective moment mu(eff) = 5.91 M.B. EPR spectra at 298, 77 and 4 K show an isotropic signal at g = 2.01. Reaction of the ligand H2DCP in a neu tral environment leads to the formation of a binuclear complex [Mn-2(D CP)(2)(H2O)(4)] with a ratio of Mn(II)/ligand of 2:2. The binuclear co mpound is weakly antiferromagnetic, J = -1.068 (7) cm(-1) and g = 2.01 . The EPR spectrum of [Mn-2(DCP)(2)(H2O)(4)] in acetonitrile solution at 4 K reveals the fine structure of the Mn (II) ion.