A cyano-bridged copper(ii)–copper(i) mixed-valence coordination polymer as a source of copper oxide nanoparticles with catalytic activity in C–N, C–O and C–S cross-coupling reactions

Abstract

A cyano-bridged copper(II)–copper(I) mixed valence polymer, namely {[Cu₄(CN)₅(C₅H₅N)₄]}_n (1), was synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, differential scanning calorimetric analysis, and single crystal X-ray crystallography. Single crystal X-ray studies show that the coordination polymer 1 is linked by the cyanide anions with μ-1κN:2κC bridging modes to the copper centers, generating a two-dimensional (2D) layered network. The coordination polymer 1, upon pyrolyzing, yielded copper oxide nanoparticles, which have been characterized by TEM and powder X-ray diffraction. The catalytic properties of the resulting copper oxide nanoparticles have also been studied in C–N, C–O, and C–S cross-coupling reactions with aryl halides. The C–N, C–O and C–S coupling products were obtained in moderate to good yields (66–90%, 72–98%, and 50–86%), respectively.