A Classical Silver Carbonyl Complex [{MeB[3-(Mes)pz]3}Ag(CO)] and the Related Silver Ethylene Adduct [{MeB[3-(Mes)pz]3}Ag(C2H4)]

摘要

Silver complexes of small unsaturated molecules such as carbon monoxide and ethylene are of tremendous fundamental importance and practical value. Yet, structurally characterized silver(I) complexes featuring CO and C2H4 ligands are rare. The isolation of such thermally stable adducts is a very challenging task because silver(I) is a poor π acceptor, a poor π donor, and in general forms extremely labile adducts with π-acidic ligands. The light sensitivity of silver adducts, the oxidizing nature of silver, and the easy displacement of the coordinated CO and C2H4 ligands by many other weakly donating species (which includes common solvents) present further synthetic challenges. The entropic factors arising from fixing gases are also believed to play a detrimental role.