Practical and highly enantioselective synthesis of beta-alkynyl-beta-amino esters through Ag-catalyzed asymmetric mannich reactions of silylketene acetals and alkynyl imines

Org Lett. 2005 Jun 23;7(13):2711-3. doi: 10.1021/ol050910r.

Abstract

[reaction: see text] A readily available iso-leucine-based phosphine ligand is used to promote Ag-catalyzed Mannich reactions between silylketene acetals and various alkynyl imines. Reactions can be effected in the presence of 5 mol % catalyst, without the need for rigorous exclusion of air, and with commercially available solvents (without purification) to afford the desired beta-alkynyl-beta-amino esters in 84-94% ee and 61-91% isolated yield.

Publication types

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

MeSH terms

  • Acetals / chemistry
  • Alkynes / chemical synthesis*
  • Alkynes / chemistry*
  • Amino Acids / chemical synthesis*
  • Catalysis
  • Esters
  • Imines / chemistry
  • Indicators and Reagents
  • Molecular Structure
  • Silanes / chemistry
  • Silver / chemistry
  • Stereoisomerism

Substances

  • Acetals
  • Alkynes
  • Amino Acids
  • Esters
  • Imines
  • Indicators and Reagents
  • Silanes
  • Silver