Structural Characterization and Spectroscopic Properties of Luminescent Silver(I) and Copper(I) Complexes bearing Phosphine and Cyanide Ligands

Abstract

Reaction of equimolar amounts of AgCN and PCy3 gave the [(Cy3P)Ag(NCAgCN)]¥ polymer, whereas excess PCy3 yielded the discrete [(Cy3P)2Ag(NCAgCN)] compound. Reacting bis(dicyclohexylphosphino)methane with AgCN yielded the crystalline complex [Ag2(m-dcpm)2][Ag(CN)2]2. A similar reaction of CuCN with PCy3 afforded the polymeric compound [{(Cy3P)CuCN}3]¥, whereas reaction of CuCN with dcpm yielded the binuclear species [Cu2(m-dcpm)2(CN)2]. Employment of 1,2-bis(dicyclohexylphosphino)ethane and 1,3-bis(diphenylphosphino)propane in reactions with [Cu(CH3CN)4]PF6 afforded the macrocylic compounds [{Cu(dcpe)}2(CN)(m-dcpe)]PF6 and [{Cu(dppp)}3(CN)2(m-dppp)]PF6 respectively. The hexanuclear complex [Cu(CN)(PCy3)]6 was obtained by reacting CuCN with PCy3 in the presence of sodium pyridine-2-thiolato. Intense absorption bands at lmax 257–276 nm for the binuclear derivatives are assigned to nds* ® (n + 1)ps transitions. The intense MeOH/EtOH (1:4) glassy emissions at 77 K for these complexes occur at lmax 382–416 nm and can be attributed to metal-centered excited states.