Reactions of CO2 with Cu(I) Alkoxides and Amides to Give Alkylcarbonato-, μ-Carbonato-, Hydrogencarbonato-, and Carbamato-copper Complexes

Article abstract of DOI:10.1246/bcsj.53.680

Carbon dioxide reacts with ROCu(PPh3)2 (R = C2H5, C6H5CH2; PPh3 = triphenylphosphine) to produce ROCO2Cu(PPh3)2.Hydrolysis or thermolysis of the alkylcarbonatocopper(I) complexes gives a binuclear carbonatocopper(I) complex (PPh3)2CuOCO2Cu(PPh3)2, which is further converted into a hydrogencarbonatocopper(I) complex n by the reaction with CO2 in most solvents.The IR spectrum of n shows association of the HOCO2Cu(PPh3)2 units through hydrogen bonds.The IR spectrum of n also reveals that the mode of the association depends on conditions of the crystallization of the complex.The reaction of (PPh3)2CuOCO2Cu(PPh3)2 with CH3I gives (CH3O)2CO and the reaction of n with C6H5NH2 affords C6H5NHCO2Cu(PPh3)2 in high yields.Carbon dioxide reacts also with an amidocopper(I) complex C6H5NHCu(PPh3)2 to yield a carbamatocopper(I) complex C6H5NHCO2Cu(PPh3)2.The reaction of CH3Cu(PPh3)2 (diethyl ether)_0.5 with CO2 in the presence of HN(C2H5)2 affords (C2H5)2NHCO2Cu(PPh3)2.The isocyanate group of phenyl isocyanate is inserted into the C2H5O-Cu bond of C2H5OCu(PPh3)2 to give a (ethyl N-phenylcarbamato)copper complex.