Preparation of Enantiomerically Pure Perfluorobutanesulfinamide and Its Application to the Asymmetric Synthesis of α-Amino Acids

J Org Chem. 2016 Feb 19;81(4):1547-57. doi: 10.1021/acs.joc.5b02700. Epub 2016 Feb 4.

Abstract

A high yielding and practical two-step synthesis of enantiomerically pure perfluorobutanesulfinamide from Senanayake's 2-aminoindanol-derived sulfinyl transfer reagent was developed and carried out on a multigram scale. Straightforward condensation of this sulfinamide with ethyl glyoxylate provided the N-perfluorobutanesulfinyl imino ester. The utility of this activated N-sulfinyl imino ester was demonstrated for reactions that gave either no product or very low yields with the corresponding less electrophilic N-tert-butanesulfinyl derivative. Specifically, the Rh(III)-catalyzed C-H bond addition of aromatic compounds to the N-perfluorobutanesulfinyl imino ester provided arylglycines with very high diastereoselectivities for a range of directing groups including pyrrolidine amide, azo, sulfoximine, 1-pyrazole, and 1,2,3-triazole functionalities. Thermal asymmetric aza-Diels-Alder reactions also proceeded in good yields and with high selectivity, including for the substituted dienes (E)-1,3-pentadiene and (2E,4E)-2,4-hexadiene.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alkadienes / chemistry*
  • Amino Acids / chemical synthesis*
  • Amino Acids / chemistry
  • Cyclization
  • Molecular Structure
  • Stereoisomerism
  • Sulfonamides / chemical synthesis*
  • Sulfonamides / chemistry

Substances

  • Alkadienes
  • Amino Acids
  • Sulfonamides