CARBAMOYL COMPLEXES AS A SOURCE OF ISOCYANATES OR CARBAMYL CHLORIDES

Isocyanates or carbamyl chlorides have been prepared by reaction of ca rbamoyl complexes of nickel and palladium with CuCl2. Isocyanates are selectively produced from the carbamoyl complexes of primary amines, [ LNiCl(CONHR)], (L = 2,6-bis(diphenyl-phosphinomethyl) pyridine; R = C6 H5, P-CH3C6H4, or P-ClC6H4)) and [Pd(PPh3)2Cl(CONHCH2COOCH3)], whereas carbamoyl complexes of secondary amines, such as [Pd(PPh3)2Cl(CO(CH2) 4CH2)], afford carbamyl chloride. As expected, the reaction of the res ulting isocyanates or carbamyl chlorides in situ with alcohols or amin es produces carbamates or N,N'-substituted ureas, respectively.