Rhodium complex of monodentate phosphite as a catalyst for olefins hydroformylation

Abstract

Rhodium complex of a novel monodentate bulky phosphite ligand, tri-1-naphthylphosphite is studied for the hydroformylation of dissimilar alkenes specifically, 1-hexene, styrene, and cyclohexene. The steric attributes of free ligand is investigated by cone angle. The effect of concentration of alkene as well as catalyst, ligand/Rh ratio, pCO and pH 2 on the rate of reaction has been studied. For 1-hexene and styrene, the initial rate was found to be zero order with respect to initial alkene concentration and first order with respect to catalyst concentration and H 2 partial pressure. For cyclohexene, the reaction was found to be first order with respect to the initial cyclohexene concentration and of slightly positive order with respect to H 2 partial pressure. The initial rate of hydroformylation of styrene (at 80 °C, 3.0 MPa syngas pressure) is ∼3.9 times less than that of 1-hexene hydroformylation where as the rate of cyclohexene hydroformylation is ∼87 times less than that of 1-hexene hydroformylation.