Synthesis of enantiopure trans-2,5-disubstituted trifluoromethylpyrrolidines and (2S,5R)-5-trifluoromethylproline

J Org Chem. 2015 Mar 6;80(5):2700-8. doi: 10.1021/jo502885v. Epub 2015 Feb 13.

Abstract

Enantiopure trans-2,5-disubstituted trifluoromethylpyrrolidines were prepared on a several gram scale starting from a readily available chiral fluorinated oxazolidine (Fox). A pure oxazolopyrrolidine intermediate could be obtained after an efficient separation by selective diastereomer destruction. The addition of various Grignard reagents on this oxazolopyrrolidine provided disubstituted pyrrolidines with moderate to complete trans diastereoselectivity. The highly valuable compound (2S,5R)-5-trifluoromethylproline could be synthesized from the same oxazolopyrrolidine intermediate via a Strecker-type reaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Hydrocarbons, Fluorinated / chemical synthesis*
  • Hydrocarbons, Fluorinated / chemistry
  • Indicators and Reagents / chemistry
  • Molecular Structure
  • Oxazoles / chemistry*
  • Proline / analogs & derivatives*
  • Proline / chemical synthesis
  • Proline / chemistry
  • Pyrrolidines / chemical synthesis*
  • Pyrrolidines / chemistry
  • Stereoisomerism

Substances

  • 5-trifluoromethylproline
  • Hydrocarbons, Fluorinated
  • Indicators and Reagents
  • Oxazoles
  • Pyrrolidines
  • oxazolidine
  • Proline