METALLOGANDS .3. STUDIES ON SOME HOMO HETERO TRINUCLEAR NICKEL(II), COBALT(II) AND COPPER(II) COMPLEXES OF 1,12-DIOXO-6,7-DIPHENYL-1,3,5,7,9,11-DODECAHEXENE/

A series of homo/hetero trinuclear complexes of the type [M Ni M (TTDD )(2)X(2) (H2O)(n)] where M = nickel(II), cobalt(II) and copper(II), X = Cl-, Br- and NO3-, n = 0 or 4 and TTDD 4,5,8,9-tetraza-1,3,10, 12-te tramethyl-1, 12-dioxo-6,7-diphenyl-1,3,5,7,9,11-dodecahexene have been prepared in a stepwise reaction from the precursor Ni(II) bis-(benzil -dihydrazone) complexes and are characterised by elemental analyses, I R, UV/vis spectra, magnetic moments, molar conductances and thermal an alyses. An approximately octahedral geometry around the metal(II) ions is proposed for all the complexes except Ni-Ni-Ni system where square planar geometry is proposed for the terminal metal(II) ions. Differen t ligand field parameters and the tetragonal splitting parameters have been estimated. The complexes containing Cu(II) ions have been screen ed against some fungal pathogens as possible fungicides.