Catalytic Hydrogenation of Carboxamides with a Bifunctional Cp*Ru Catalyst Bearing an Imidazol-2-ylidene with a Protic Aminoethyl Side Chain

Synthesis of a Cp*Ru complex bearing an NH 2 -functionalized N -heterocyclic carbene (C–N H ) was achieved by treatment of Cp*RuBr(isoprene) with an equimolar amount of a silver complex, which was generated from Ag 2 O and 1-(2-aminoethyl)-3-methylimidazolium bromide, in CH 3 CN at room temperature. The new Cp*RuBr(C–N H ) complex showed a higher catalytic performance than the related Cp*RuCl(P–N H ) and Cp*RuCl(N–N H ) complexes. In the reaction of N -arylcarboxamides, the amine products were obtained in satisfactory yields under mild temperature conditions.