Catalytic C-H activation of phenylethylamines or benzylamines and their annulation with allenes

J Org Chem. 2014 Oct 17;79(20):9578-85. doi: 10.1021/jo501658s. Epub 2014 Oct 1.

Abstract

Tetrahydro-3-benzazepines and tetrahydroisoquinolines are synthesized in one step from allenes and phenylethylamines or benzylamines, respectively. Mechanistically, it is assumed that activation of a C-H bond of an aromatic ring with Pd(II) occurs, directed by the primary amine, leading to the formation of a palladacycle into which an allene then undergoes insertion. The resulting π-allyl intermediate cyclizes to the products by an intramolecular allylic alkylation. The process is particularly useful with 2,3-butadienoates and amines having a quaternary carbon at the α-position.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkadienes / chemistry*
  • Alkylation
  • Benzylamines / chemistry*
  • Butadienes / chemistry*
  • Catalysis
  • Cyclization
  • Hydrogen Bonding
  • Molecular Structure
  • Palladium / chemistry
  • Phenethylamines / chemistry*

Substances

  • Alkadienes
  • Benzylamines
  • Butadienes
  • Phenethylamines
  • propadiene
  • Palladium