Synthesis and characterization of new co(II)‎,Ni(II)‎,Cu(II)‎ and Zn(II)‎ complexes with benzil bis-hydrazone ligands

الملخص EN

A number of new Co(II), Ni(II), Cu(II) and Zn(II) complexes with benzil bis(acetoyl hydrazone) (BNAH), benzil bis(picolinoyl hydrazone) (BNPH) and benzil bis(2-theonyl hydrazone) (BNTH) have been prepared.

The bis-hydrazone ligands were synthesized by the condensation of benzil with (acetyl hydrazide, picolinic acid hydrazide or 2-thiophene carbohydrazide ) in 1:2 molar ratio.

The reaction of metal(II) acetate with the ligands in (1:1) molar ratio in ethanol in presence of triethylamine lead to isolation of complexes having the general formula [M(L-2H)(H2O)2] [Ni(L-2H)] where (M= Co(II),Ni(II),Cu(II) and Zn(II)) , and (L-2H=doubly deprotonated ligands BNAH, BNTH and BNPH), The ligands and complexes have been characterized by spectral (IR,UV-Vis), elemental analysis, (1H-NMR), magnatic and molar conductance measurements, which revealed that the ligands BNAH, BNTH and BNPH acts as dinegtive charge tetradentate (NNOO-2 ) donor ligands in the metal complexes, coordinated through the two azomethine group nitrogen atoms and the two enolic oxygen atoms .

All complexes provide an octahedral geomatry exept [Ni(L-2H)] is provide an square planer geometry-