Highly selective hydroformylation of internal and terminal olefins to terminal aldehydes using a rhodium-BIPHEPHOS-catalyst system

2-Pentene was hydroformylated to 1-hexanal with a rhodium-phosphite-ligand-system with high conversion. The catalytic system with the ligand BIPHEPHOS is able to synthesize aldehydes easily from terminal olefins (C5-C12) with high TONs and TOFs, and with lower activities from internal olefins, in both cases with high regioselectivities of linear:branched ratio up to 99:1. For 1-dodecene a TOF of 44,000 h−1 was achieved.