Abstract
There has been much recent interest in the use of cationic rhodium (I) complexes that contain chelating diphosphine ligands for catalytic hydrogenation1-4 and decarbonylation5-7 reactions. Results from our laboratory on the catalytic decarbonylation of aldehydes using [Rh(diphosphine)2]+ complexes strongly implicate a mechanism that involves an initial Rh-P bond rupture that leads to a catalytically active three-coordinate complex.7,8 In order to test this possibility, a study that makes use of complexes of chelating phosphorus-nitrogen (PN) donor ligands was initiated. With such ligands the N donor end is known to be labile.9 As part of this general investigation a PNP ligand was synthesized.