title: Selective defluorination approach to N-Cbz-3,3-difluoro-2-difluoromethylenepyrrolidine and its application to 3,3-difluoroproline dipeptide synthesis.
abstract: Mg-promoted defluorination of N-(p-methoxyphenyl)bis(trifluoromethyl)imine 1 gave perfluoroenamine 2, which was readily transformed to N-Cbz-2-trifluoromethyl-3,3-difluoropyrrolidine 10. Chemoselective defluorination from the trifluoromethyl group of 10 by LHMDS-promoted dehydrofluorination in THF provided 3,3-difluoro-2-difluoromethylenepyrrolidine 11. The product 11 was converted to 3,3-difluoroproline dipeptides 16 upon treatment with aminoesters.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Okayama University, 3-3-1 Tsushima-naka, Okayama, 700-8530 Japan.
authors.forename: Yong
authors.initials: Y
authors.lastname: Guo
authors.forename: Kana
authors.initials: K
authors.lastname: Fujiwara
authors.forename: Hideki
authors.initials: H
authors.lastname: Amii
authors.forename: Kenji
authors.initials: K
authors.lastname: Uneyama
mesh_terms: D004151:Dipeptides / Q000138:chemical synthesis* / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry*; D015394:Molecular Structure; D011392:Proline / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D011759:Pyrrolidines / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D004151:Dipeptides; D006845:Hydrocarbons, Fluorinated; D011759:Pyrrolidines; D011392:Proline