G. Consiglio, F. Morandini, M. Scalone
Jan 8, 1985
Citations
0
Influential Citations
63
Citations
Journal
Journal of Organometallic Chemistry
Abstract
Abstract Some mono- and disubstituted ethenes have been asymmetrically hydroformylated with rhodium and platinum catalysts using (2 S ,3 S )-2,3-bis(diphenylphosphino)butane (Chiraphos) as the chiral ligand (maximum optical yield ∼ 45%). The results are compared with those obtained when the chiral ligand is (4 R ,5 R )-2,2-dimethyl-4,5-bis(diphenylphosphinomethyl)-1,3-dioxolane (Diop). The Chiraphos ligand causes a decrease of the catalytic activity with respect to Diop. Optical yields for rhodium catalysts are always higher with Chiraphos, whereas scattered results were obtained with platinum catalysts. Since for the catalytic systems examined asymmetric induction takes place before or during the formation of the intermediate diastereomeric metal alkyl complexes, the results are tentatively rationalized on the basis of a stereochemical model for the transition state leading to the above metal alkyl complexes intermediate.