Spectral studies of copper(II) complexes of tridentate acylhydrazone ligands with heterocyclic compounds as coligands: X-ray crystal structure of one acylhydrazone copper(II) complex

Six copper(II) complexes of 2-hydroxy-4-methoxybenzaldehyde nicotinoylhydrazone (H2hmbn), 2-hydroxy-4-methoxyacetophenone nicotinoylhydrazone (H2hman), 2-hydroxy-4-methoxybenzaldehyde benzoylhydrazone (H2hmbb) and 2-hydroxy-4-methoxyacetophenone benzoylhydrazone (H2hmab) have been synthesized. The complexes viz. Cu(hmbn)](2)·2H(2)O (1), Cu(hman)](2) (2), Cu(hmbb)](2)·2H(2)O (3), Cu(hmbb)phen]·1(1/2)H2O (4), Cu(hmbb)(bipy)·H2O] (5) and Cu(hmab)phen] (6) were characterized by different physicochemical techniques. The crystal structure of Cu(hman)phen] is obtained and it has a distorted square pyramidal geometry with π-π stacking interactions and significant C-H π interactions.