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

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• 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.

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 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 as PowerPoint slide