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.