Synthesis, crystal structures, and antimicrobial activity of two thiocyanato-bridged dinuclear copper(II) complexes derived from 2,4-dibromo-6-[(2-diethylaminoethylimino)methyl]phenol and 4-nitro-2-[(2-ethylaminoethylimino)methyl]phenol

Abstract

A pair of structurally similar thiocyanatobridged dinuclear Cu(II) complexes derived from the Schiff bases 2,4-dibromo-6-[(2-diethylaminoethylimino) methyl]phenol and 4-nitro-2-[(2-ethylaminoethylimino) methyl]phenol has been prepared and characterized by physico-chemical and spectroscopic methods. Each Cu atom is five-coordinate in a square-pyramidal geometry, with one O and two N atoms of one Schiff base ligand and one N atom of a bridging thiocyanate ligand defining the basal plane, and with one terminal S atom of another bridging thiocyanate ligand occupying the apical position. Antimicrobial activities of the Schiff bases and the two complexes have been tested.

Synthesis, Crystal Structures and Spectra Properties of Two New Cu(II) Complexes Containing Thiocyanato Anions as Ancillary Ligand

“…In the dimeric unit, two Cu(II) ions are bridged by two thiocyanate ligands in an end-to-end fashion with the Cu···Cu separation of 5.535 Å, which is similar to other Cu(II) complexes with double end-to-end thiocyanate bridges. 22 One S atom and one N atom from two different bridging thiocyanate ligands, and three N atoms from one tridentate ligand L coordinate to the Cu(II) ion to complete a distorted square pyramidal geometry by the τ parameter of 0.073. 21 In the basal plane, the Cu-N bond lengths are in the range of 1.946(10) to 2.041(11) Å.…”

“…The S of SCNoccupies the apical position with the Cu-S distance of 2.878 Å, which is similar to that reported for thiocyanate bridging nickel complexes. 15,22,23 The SCNgroup is linear with an S-C-N angle of 178.4°. The Cu-S-C and Cu-N-C angles for bridging SCNgroups are 94.9 and 162.8°, respectively.…”