METALLO LIGANDS .5. HOMO AND BIMETALLIC TRINUCLEAR COMPLEXES OF COPPER(II), NICKEL(II) AND COBALT(II) WITH 4,5-DIPHENYL-2,3,6,7-TETRAZAOCTAN-1,3,5,7-TETRAENE

A series of homo/bimetallic (hetero) trinuclear complexes of the type [M Cu ML(2)X(2)(H2O)(n)] where M copper(II), nickel(II) and cobalt(II) , H(2)L = -hydroxyphenyl)-4,5-diphenyl-2,3,6,7-tetrazaoctan- 1,3,5,7-t etraene, X = Cl-, Br- and NO3-, n = 0 or 4 have been isolated in a ste pwise reaction from the precursor bis(1,2-diphenylethane-1,2-dione-dih ydrazone) copper(II) complexes. The complexes have been characterised on the basis of elemental analyses, spectral, magnetic, conductivity a nd thermal studies. Most of the complexes contain coordinated water an d have low molar conductivity. The metal centres have an approximately octahedral symmetry around them except Ni-Cu-Ni system, where a squar e planar geometry has been proposed around terminal nickel centre. Dif ferent spectral parameters have also been calculated. The homo trinucl ear copper(II) complexes exhibit significant fungitoxicity.