Allylic and vinylic carbonylation of cyclohexene catalysed by [Ru(II)(EDTA-H)(CO)]

Abstract

The complex [Ru(II)(EDTA-H)(CO)] (EDTA = ethylenediaminetetraaceticacid) catalyses the carbonylation of cyclohexene in alcohol:water (80:20) mixture to give cyclohexene-1-carboxaldehyde, cyclohexene-3 carboxaldehyde and cyclohexane-carboxaldehyde. The optimum conditions of the reaction are 120“C and 20 atm CO partial pressure. The effect of catalyst, CO pressure and cyclohexene concentration on the initial rates of carbonylation was investigated. The rate of carbonylation exhibits first-order dependence with respect to catalyst, CO pressure and substrate concentration. The effect of temperature on the rate of cyclohexene carbonylation was studied and the activation energy, Ea, evaluated at 16 + or - 1 Kcal mol-1. Carbonylations of l-methyl-, 3-methyl- and 4-methylcyclohexenes conducted at 160°C and 20atm CO partial pressure gave the corresponding alcohols.