Ruthenium Carbonyl Catalyzed Reductive Carbonylation of Aromatic Nitro Compounds. A Selective Route to Carbamates

Article abstract of DOI:10.1021/jo00241a023

Ru3(CO)12 (1) and Ru(CO)3(PPh3)2 (2) catalyze the reductive carbonylation of nitrobenzene and of substituted aromatic mononitro compounds to give the corresponding methylcarbamates, in toluene-methanol, at 160-170 deg C and 60 atm, with high selectivity, in the presence of NEt4⁺Cl^- as cocatalyst.Compound 1 also catalyzes the conversion of 2,4-dinitrotoluene into the corresponding dicarbamate although less efficiently.The effects of CO pressure, reaction temperature, and amount and nature of the added alcohol and cocatalyst have been studied.The mechanism of the reaction catalyzed by 1 has been investigated by studying the reactivity and catalytic activity of possible intermediates