title: Straightforward synthesis of (S)- and (R)-alpha-trifluoromethyl proline from chiral oxazolidines derived from ethyl trifluoropyruvate.
abstract: [Structure: see text] A concise synthesis of both enantiomers of alpha-Tfm-proline and (S)-alpha-Tfm-prolinol from ethyl trifluoropyruvate is reported. The key step is a diastereoselective allylation reaction of ethyl trifluoropyruvate and (R)-phenylglycinol-based oxazolidines or imine. The lactone obtained by cyclization of the resulting hydroxy ester proved to be a valuable intermediate for the synthesis of (S)-alpha-Tfm-allylglycine and (S)-alpha-Tfm-norvaline in enantiopure form.
authors.affiliation: Laboratoire Synthèse Organique Sélective et Chimie Organométallique (SOSCO), UMR CNRS 8123, Université de Cergy-Pontoise, 5, Mail Gay-Lussac-Neuville sur Oise 95031, Cergy-Pontoise Cedex, France.
authors.forename: Grégory
authors.initials: G
authors.lastname: Chaume
authors.forename: Marie-Céline
authors.initials: MC
authors.lastname: Van Severen
authors.forename: Sinisa
authors.initials: S
authors.lastname: Marinkovic
authors.forename: Thierry
authors.initials: T
authors.lastname: Brigaud