Highly enantioselective synthesis of atropisomeric anilide derivatives through catalytic asymmetric N-arylation: conformational analysis and application to asymmetric enolate chemistry

J Am Chem Soc. 2006 Oct 4;128(39):12923-31. doi: 10.1021/ja064026n.

Abstract

In the presence of (R)-DTBM-SEGPHOS-Pd(OAc)(2) catalyst, N-arylation (aromatic amination) of various o-tert-butylanilides with p-iodonitrobenzene proceeds with high enantioselectivity (88-96% ee) to give atropisomeric N-(p-nitrophenyl)anilides having an N-C chiral axis in good yields. Atropisomeric anilide products highly prefer to exist as the E-rotamer which has trans-disposed o-tert-butylphenyl group and carbonyl oxygen. The application of the present catalytic enantioselective N-arylation to an intramolecular version gives atropisomeric lactam derivatives with high optical purity (92-98% ee). The reaction of the lithium enolate prepared from the atropisomeric anilide and lactam products with various alkyl halides gives alpha-alkylated products with high diastereoselectivity (diastereomer ratio = 13:1 to 46:1).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amination
  • Anilides / chemical synthesis*
  • Anilides / chemistry
  • Catalysis
  • Crystallography, X-Ray
  • Molecular Conformation
  • Nitrobenzenes / chemistry*
  • Palladium / chemistry
  • Stereoisomerism

Substances

  • Anilides
  • Nitrobenzenes
  • Palladium