Journal of Molecular Catalysis A-Chemical, Vol.168, No.1-2, 53-59, 2001
(R, R)-N-phenyl-3,4-bis(diphenylphosphino)pyrrolidine: an N-aryl pyrrolidine ligand for enantioselective transfer hydrogenation
The N-aryl pyrrolidine diphosphine (R. R)-N-phenyl-3,4-bis(diphenylphosphino) pyrrolidine was obtained from natural tartaric acid. Contrary to our preliminary expectations, this new chiral ligand proved to be less selective than the corresponding N-benzyl pyrrolidine diphosphine. An attempted explanation of the observed behaviour based on the stereochemistry of the ligand as shown by X-ray crystallography is presented.
Keywords:transfer hydrogenation;pyrrolidine diphosphine;asymmetric catalysis;five-membered chelate;rhodium