Dual catalytic systems for consecutive isomerization-hydroformylation reactions

A concept for the homogeneous hydroformylation of internal olefins to linea r aldehydes is presented. The internal olefin is isomerized to its terminal isomer by one catalyst prior to hydroformylation by a second transition me tal catalyst. The terminal olefins obtained by isomerization react preferen tially to give linear aldehydes. The viability of the concept is demonstrat ed by a dual catalytic Ru/Rh system with chelating phosphanophosphite ligan ds. Thus, the isomerization - hydroformylation sequence represents a promis ing starting point for the economically important refinement of internal ol efins.