New tetraphosphite ligands for regioselective linear hydroformylation of terminal and internal olefins

We successfully developed new tetraphosphite ligands L1-L5 and applied them to the rhodium-catalyzed hydroformylation of terminal and internal olefins. High catalytic reactivities and excellent regioselectivities for linear aldehydes were obtained in the rhodium-catalyzed hydroformylation of simple olefins (l/b ratio up to 90, 98.9% linear selectivity, 99.2% conversion) using the tetraphosphite ligand L2. And the tetraphosphite ligand L2 also displayed moderate to good linear regioselectivities for challenging substrates styrene and internal olefin 2-octene.