Single end-on azido bridged 1D chain copper(II) complex: Synthesis, X-ray crystal structure and catalytic activity in homogeneous epoxidation of cyclooctene

A new azido derivative of a NNO donor tridentate Schiff-base copper(II) complex, [CuL(μ1,1-N3)]n (1) (HL = 1-(N-ortho-hydroxyacetophenimine)-2-(N-ethyl)aminoethane), containing a single end-on μ1,1-azido bridged 1D infinite chain has been synthesized and characterized. X-ray single crystal structure analysis reveals that the complex [CuL(μ1,1-N3)]n (1) is a 1D chain in which neighboring Cu(II) chromophores are related by glide planes and linked by single azido bridges in the EO mode. No measurable magnetic interaction was evidenced in the complex [CuL(μ1,1-N3)]n (1) through variable temperature magnetic susceptibility measurements (10–300 K). The complex was used as an active catalyst for the epoxidation of cyclooctene using tert-butyl-hydroperoxide as an oxidant. The catalytic activity of the complex has been compared in a series of solvents. The results show that in acetonitrile medium, the epoxide was produced in high yield with high selectivity.

Graphical abstractA copper(II) azido complex containing a tridentate Schiff-base (NNO donor) ligand has been synthesized and characterized by single crystal X-ray diffraction analysis. Epoxidation reactions of cyclooctene catalyzed by this complex, in different solvent media, have been studied using tert-BuOOH as the oxidant. The results show that in acetonitrile medium, the epoxide was produced in high yield with high selectivity.Figure optionsDownload full-size imageDownload as PowerPoint slide