Katalytische isomerisierung von heptenen mit IrX(CO)L2

Abstract 1-, 2- cis -, 2- trans -, and 3- trans -heptenes (C 7 )are isomerized either very slowly or not at all with IrX(CO)L 2 at 80°C in toluene and under N 2 . However, under the conditions of hydrogenation fast isomerisation takes place. With IrCl(CO)L 2 as catalyst the rate of isomerisation decreases the order: 1-C 7 ∼ 2- cis -C 7 > 3- trans -C 7 > 2- trans -C 7 . This sequence is independent of the ligand L in lrCl(CO)L 2 , however, with a particular isomer the rate of isomerisation is a function of L in the order L = PPh 3 > P(C 6 H 11 )3 > P(OPh) 3 . The overall rate of hydrogenation of an olefin depends on the rate of isomerisation. and hydrogenation of all isomers formed during hydroisomerisation.