title: Highly enantioselective synthesis of 5-phenyl-2-alkylprolines using phase-transfer catalytic alkylation.
abstract: An efficient enantioselective synthetic method for the synthesis of (2R)-5-phenyl-2-alkylproline tert-butyl esters was reported. The phase-transfer catalytic alkylation of tert-butyl-5-phenyl-3,4-dihydro-2H-pyrrole-2-carboxylate in the presence of chiral quaternary ammonium catalysts gave the corresponding alkylated products (up to 97% ee). The following diastereoselective reductions afforded chiral 5-phenyl-2-alkylprolines which can be applied to asymmetric synthesis as organocatalysts or synthesis of biologically active proline based compounds, such as chiral α-alkylated analogues of (+)-RP66803, as potential CCK antagonists.
authors: Research Institute of Pharmaceutical Science and College of Pharmacy, Seoul National University, Seoul 151-742, Korea.
authors: Myungmo
authors: M
authors: Lee
authors: Young-Ju
authors: YJ
authors: Lee
authors: Eunyoung
authors: E
authors: Park
authors: Yohan
authors: Y
authors: Park
authors: Min Woo
authors: MW
authors: Ha
authors: Suckchang
authors: S
authors: Hong
authors: Yeon-Ju
authors: YJ
authors: Lee
authors: Taek-Soo
authors: TS
authors: Kim
authors: Mi-hyun
authors: MH
authors: Kim
authors: Hyeung-geun
authors: HG
authors: Park
mesh_terms: D000478:Alkylation; D002384:Catalysis; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D044367:Phase Transition; D011392:Proline / Q000031:analogs & derivatives / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D011392:Proline