KINETICS AND MECHANISM OF THE REDUCTIVE CARBONYLATION OF NITROBENZENE CATALYZED BY DICHLOROBIS(SALICYLALDEHYDE)-ORTHO-PHENYLENEDIIMINATORUTHENATE(III)

The complex [Ru(saloph)Cl2] (saloph = bis(salicylaldehyde)-o-phenylenediimine) catalyzes the reductive carbonylation of nitrobenzene in ethanol to one exclusive product, phenylurethane. The reaction proceeds at mild conditions of 15 atm CO and 160 °C with a turnover rate of 80 mol product per mol catalyst per hour. The rates of carbonylation of nitrobenzene measured at 160 °C and 3 - 15 atm CO partial pressure were found to exhibit first-order dependences with respect to catalyst, dissolved CO and nitrobenzene concentrations. The rates of the reductive carbonylation of nitrobenzene were measured in the temperature range 140 - 160 °C and the activation energy Ea was calculated as 38 kcal mol-1. © 1990.