Synthesis, Structural Characterization and Electrochemical Studies of a Nicotinamide‐bridged Dinuclear Copper Complex derived from a Tridentate Hydrazone Schiff Base Ligand

The in‐situ formed hydrazone Schiff base ligand ( E )‐ N ′‐(2‐hydroxy‐3‐methoxybenzylidene)benzohydrazide (H 2 L 1 ) and nicotinamide (L 2 ) give the copper(II) complex [CuL 1 L 2 ] on reaction with copper(II) acetate. In the solid state two copper atoms are linked by nicotinamide through coordination with its pyridyl nitrogen atom and its amide‐C=O group to the dicopper(II) complex [CuL 1 (μ‐L 2 )CuL 1 L 2 ]. The coordination polyhedra are a CuO 2 N 2 square and a CuO 3 N 2 square pyramide. Cyclic voltammetric experiments of the solution species [CuL 1 L 2 ] in DMF reveal reduction of the L 1 ligand at three potentials with a reduction at −0.5 V resulting in decomposition of the complex.