Copper(I) complexes of new N2S2 donor Schiff-base ligands derived from 1,2-bis-(2-amino-phenylsulfanyl)ethane

Highlight•Two new S2N2 Schiff base ligands L1 and L2 have been synthesized and characterized.•The Cu(I) complexes of L1 (1) and L2 (2) have been synthesized and structurally characterized.•L1 and L2 act as bis-bidentate chelating ligands coordinating to two Cu(I) in an anti-form.•(1) is a centrosymmetric dimer with pairs of Cu(PPh3)(I) units bridged by L1.•(2) is a 1-dimensional Cu(I) coordination polymer with a μ2-bridging ligand [(μ-I)2].

A dinuclear copper(I) complex, [{Cu(PPh3)(I)}2((μ-L1)] (1), and a one-dimensional copper(I) coordination polymer, [Cu2(μ-I)2(μ-L2]n (2), with two new Schiff base ligands, L1 = 1,2-bis-[2-(trans-phenylcinnamaldimino)-phenylsulfanyl]-ethane, L2 = 1,2-bis-[2-(benzaldimino)-phenylsulfanyl]-ethane have been synthesized. The ligands L1 and L2 have been prepared by the condensation of 1,2-bis-(2-aminophenylsufanyl)-ethane with β-phenyl-cinnamaldehyde and benzaldehyde respectively. The ligands and their copper complexes have been characterized by elemental analyses, FT-IR, UV–Vis and 1H NMR spectroscopy and their structures have been fully confirmed by single-crystal X-ray analysis. The two Schiff bases act as N2S2-bis-bidentate chelating ligands coordinating to Cu(I) centers in an anti-form. The coordination geometry around Cu(I) centers in the two complexes 1 and 2 is a distorted tetrahedron. The electrochemical properties of 1 and 2 have also been investigated by cyclic voltammetry and both copper complexes show irreversible redox behavior.

Graphical abstractA dinuclear copper(I) complex, [{Cu(PPh3)(I)}2((μ-L1)] (1), and a one-dimensional copper(I) coordination polymer, [Cu2(μ-I)2(μ-L2]n (2), with two new S2N2 Schiff base ligands, have been synthesized and fully characterized. The X-ray crystal structures of (1), and (2) have been determined. Spectral and electrochemical studies are also reported.Figure optionsDownload full-size imageDownload as PowerPoint slide