Novel mono-and binuclear complexes of Cu(II) with hydrazones of salicylaldehyde derivatives

A series of new mono-and binuclear metal chelates of Cu(II) with ligands, which are the products of condensation of 3,5-di(tert-butyl)salicylaldehyde with hetarylhydrazines or 4-phenylsemi(thiosemi)carbazide, were synthesized. Their compositions and structures were determined by the elemental analysis, IR and 1H NMR spectroscopies, magnetochemistry, and conductometry measurements. It was shown for the first time that in the case of hetarylhydrazones, only mononuclear complexes were formed due to steric effect of tert-butyl fragments, whereas arylhydrazones gave binuclear complexes with two Cu atoms bonded by the spin-spin interaction. The exchange parameters 2J were calculated for binuclear metal chelates.