Ionic diamine rhodium(I) complexes—highly active catalysts for the hydroformylation of olefins

Rhodium(I) complexes composed of an anionic rhodium centre containing chloride ligands, and a cationic rhodium centre coordinated by a diamine ligand, were synthesized and characterized. These complexes are able to catalyze the hydroformylation reaction under mild reaction conditions in excellent activity and regioselectivity, and in the absence of a phosphorus ligand.