Novel cyano-bridged mixed-valent copper complexes formed by completely in situ synthetic method via the cleavage of C-C bond in acetonitrile

A series of novel cyano-bridged mixed-valent copper complexes with different nuclearities, where the cyanide group is obtained from the cleavage of a carbon-carbon (C-C) bond in acetonitrile under mild conditions, have been prepared and structurally characterized via a completely in situ synthetic method. The method is catalyzed by 2,2'-bipyridine and 1,10-phenanthroline-based Cu(II) complexes in the presence of certain reductants, such as aryl aldehydes or pyridyl amines. This work provides a facile in situ synthetic method to prepare mixed-valent cyano-bridged multinuclear complexes having novel Cu(II)(CN)Cu(I)(CN)Cu(II) and Cu(II)(CN)Cu(I)(CN)Cu(I)(CN)Cu(II) units and avoids using toxic cyanides. In addition, our preliminary studies demonstrate that the mixed-valent trinuclear copper complexes can effectively catalyze the oxidation of benzaldehyde by peroxide.