Anion-controlled syntheses and crystal structures of a pair of novel azide-bridged copper(II) complexes constructed from 4-chloro-2-[(2-dimethylaminoethylimino)methyl]phenol

A pair of novel azide-bridged polynuclear copper(II) complexes, [CuL(mu(1,1)-N-3)](n) (1) and [Cu4L2(CH3COO)(2)(mu(1,1)-N-3)(4)] (2) (L=4-chloro-2-[(2-dimethylaminoethylimino)methyllphenolate), have been obtained from the same Schiff base ligand and an identical synthetic procedure using anions of the metal salts as the only independent variable. Complex I was synthesized using copper(II) nitrate, while complex 2 was synthesized using the copper(II) acetate as the salt. Both of the complexes show novel supramolecular structures in their crystals as elucidated by X-ray analyses. The polynuclear complex I contains [CuL(mu(1,1)-N-3)](n) units as the building blocks, crystallizes in the Pbca space group. The tetra-nuclear complex 2 contains [Cu4L2(CH3COO)(2)(mu(1,1)-N-3)(4)] units as the building blocks, crystallizes in the P (1) over bar space group.