Rhodium complexes possessing S-phosphinite ligands with or without an amino group: application to hydroformylation of styrene

A chelate cationic rhodium(I) complex with a hemilabile amino- and sulfur-containing phosphinite ligand has been synthesized and, according to the NMR data, the ligand is bound to the metal in a P,S-bidentate coordination mode without any Rh–N interaction. This complex efficiently catalyzes the hydroformylation of styrene. The chelate rhodium complex with the analogous ligand without the amino group has also been synthesized and examined as a catalyst for the same hydroformylation reaction. The reaction rate is higher using the former complex compared to the latter one without the amino group, with, however, a slightly lower regioselectivity towards the formation of the branched aldehyde.