A New Bidentate Aminophosphole−Olefin Ligand for the Rhodium-Catalyzed Hydroformylation of Mono- and Disubstituted Olefins

Reaction of 1-bromo-2,5-diphenylphosphole with 10,11-dihydro-5H-dibenzo[b,f]azepine resulted in
the formation of the corresponding aminophosphole 3, which was structurally characterized. Reaction of
3 with [Rh2(μ-Cl)2(C2H4)4] and [Rh(COD)2][BF4] afforded the complexes [Rh2(μ-Cl)2(3)2] (4) and [Rh(COD)(3)][BF4] (5), respectively. In both complexes, characterized by NMR as well as by X-ray
crystallography, ligand 3 behaves as a chelate through coordination of the phosphorus atom and the
olefinic part of the ligand to the rhodium center. The activity of both complexes was tested in the
hydroformylation of mono- and disubstituted olefins at 20 bar of CO/H2 pressure. Complex 5 proves to
be the most efficient catalyst.