N,N-DISUBSTITUTED LITHIUM BIS(CARBAMOYL)CUPRATE. A CONVENIENT COMPLEX FOR ONE-POT CONVERSIONS OF AMINES TO FORMAMIDES, OXAMIDES, CARBAMATES, AND OXAMIC ACIDS

Article abstract of DOI:10.1016/0022-328X(85)80441-1

Lithium bis(carbamoyl)cuprates (2) were readily derived from secondary amines such as N-methylaniline, N-methylbenzylamine, and diethylamine, under mild carbonylation conditions (0 deg C, 1 atm of carbon monoxide), but diphenylamine and benzylphenylamine were unsuitable as the starting materials.The carbamoylcopper complexes 2 formed in ether were readily converted to the corresponding formamides, oxamides, carbamates, and oxamic acids by the appropriate treatment.The formation and stability of 2 depended much on the solvent used.The higher polarity effect of the solvent (DME, THF, and HMPA) made 2 less stable and caused concomitant evolution of carbon monoxide in further reactions.A palladium catalyst was found to be effective for cross-coupling reactions of 2 with iodobenzene or (E)-β-bromostyrene.