Copper(I) complexes with Schiff base and 1,2-bis(diphenylphosphino)ethane as ligands: Synthesis, structure and catalytic properties for the amination of aryl halide

Some copper(I) complexes of the type [Cu(L)(dppe)]X (1–4) [where L = (3-trifluoromethylphenyl)pyridine-2-ylmethylene-amine; dppe = 1,2-bis(diphenylphosphino)ethane; X = Cl−, CN−, ClO4− and BF4−] have been synthesized by the condensation of 3-aminobenzotrifluoride with 2-pyridinecarboxaldehyde followed by the reaction with CuCl, CuCN, [Cu(MeCN)4]ClO4 and [Cu(MeCN)4]BF4 in presence of dppe. The complexes 1–4 were then characterized on the basis of elemental analysis, IR, UV–Vis and 1H NMR spectral studies. The representative complex of the series 4 has been characterized by single crystal X-ray diffraction which reveal that in complex the central copper(I) ion assumes the irregular pseudo-tetrahedral geometry. The catalytic activity of the complexes was tested and it was found that all the complexes worked as effective catalyst in the amination of aryl halide.

Graphical abstractSome copper(I) complexes have been prepared by the reaction of Cu(I) salt with Schiff base and 1,2-bis(diphenylphosphino)ethane and characterized by elemental analyses, IR, UV–Vis and 1H NMR spectroscopy. Single crystal X-ray diffraction of [Cu(L)(dppe)]BF4 shows pseudo-tetrahedral geometry. All the copper(I) complexes worked as effective catalyst for the amination of aryl halide.Figure optionsDownload full-size imageDownload as PowerPoint slide