Rhodium-Biphephos-Catalyzed Tandem Isomerization-Hydroformylation of Oleonitrile

Tandem isomerization-hydroformylation of oleonitrile (an 18-carbon nitrile with a remote internal (9-)C=C bond) has been studied using Rh-bisphosphite catalyst systems, targeting formation of the linear aldehyde. The best compromise between regioselectivity (l/b = 58:42) and chemoselectivity (60%) was obtained at 120 degrees C and 10 bar CO/H-2 (1:1) with a catalyst based on Biphephos at a 0.5 mol % catalyst load and a low ligand excess (2 equiv. versus Rh). These values stand among the better reported ones for the tandem isomerization-hydroformylation of long chain olefins with a single-component catalyst system.