NICKEL-CATALYZED AMIDATION OF BROMO- AND IODOBENZENE

Article abstract of DOI:10.1016/0022-328X(87)80354-6

The carbonylation of aryl halides in the presence of p-RC6H4NH2 (R = H, CH3, Cl) or C6H5NHR (R = CH3, C2H5) and a catalytic amount of a nickel(II) or nickel(0) tertiary phosphine complex at 150 degC or above under carbon monoxide pressures is reported.Amides were obtained in high yields in reactions with p-RC6H4NH2, but with C6H5NHR compounds the expected N-alkyl benzanilides were not formed, benzanilide in low yield being formed instead.A possible catalytic cycle based on an active Ni(0)-carbonyl complex is suggested, and the observed deactivation of the catalytic system when the carbon monoxide pressure falls to 6 atm or below, is accounted for in terms of a side reaction which produces an inactive Ni(II) compound.