Dual catalytic systems for consecutive isomerization-hydroformylation reactions

A concept for the homogeneous hydroformylation of internal olefins to linear aldehydes is presented. The internal olefin is isomerized to its terminal isomer by one catalyst prior to hydroformylation by a second transition metal catalyst. The terminal olefins obtained by isomerization react preferentially to give linear aldehydes. The viability of the concept is demonstrated by a dual catalytic Ru/Rh system with chelating phosphanophosphite ligands. Thus, the isomerization - hydroformylation sequence represents a promising starting point for the economically important refinement of internal olefins.