The hydrogenation in methanol solution of the complexes. RhCl (CO) {PPh2[(CH2)n) CHCH2]}2 and PhCl(CO) [PPh2 (CH2CH2 CHCHCH3)]2.

The complexes RhCl (CO) {PPh[(CH)CHCH]} and RhCl (CO) {A figure is presented} add hydrogen in methanol solution saturating the olefin and forming RhCl (C0) {PPh [(CH)CH]}, n = 0-3. The reaction does not proceed in non-protic solvents. Carbon monoxide inhibits the reaction, whereas excess ligand (for n = 2) becomes catalytically saturated. The rate of the reaction depends largely on steric factors and follows the order RhCl (CO) [PPh (CHCHCHCH)] > RhCl (CO) [PPh(CHCHCH=CHCH)] ~ RhCl (CO) [PPh (CHCHCHCHCH)] > RhCl (CO) [PPh(CHCHCH)] > RhCl (CO) [PPh(CHCH)]. Deuteration experiments show that scrambling does occur and a mechanism for the hydrogenation is proposed. Isomerisation for n = 3 occurs at higher temperatures giving the cis-olefinphosphine complex RhCl (CO) {A figure is presented}