Stereoselective synthesis of 2,3-disubstituted indoline, pyrrolidine and cyclic ether-fused 1,2-dihydroquinoline derivatives using alkyne iminium ion cyclization of vinylogous carbamates: switch of regioselectivity using an internal hydroxy group as a nucleophile

Chem Commun (Camb). 2015 Sep 14;51(71):13623-6. doi: 10.1039/c5cc05292k.

Abstract

An intramolecular, alkyne iminium ion cyclization of vinylogous carbamates derived from o-alkynyl anilines and N-protected homopropargyl amines is developed for the stereoselective construction of trans-2,3-disubstituted indolines and pyrrolidine derivatives, respectively. The regioselectivity of the alkyne iminium ion cyclization could be switched using a hydroxy group as an internal nucleophile resulting in cyclic ether-fused 1,2-dihydroquinolines. The entire process of nitrogen heterocycle formation can also be carried out in a 'one-pot' manner starting from o-iodo aniline derivatives.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkynes / chemistry*
  • Carbamates / chemistry*
  • Cyclization
  • Ether / chemistry*
  • Imines / chemistry*
  • Indoles / chemical synthesis
  • Indoles / chemistry*
  • Ions
  • Molecular Structure
  • Pyrrolidines / chemical synthesis
  • Pyrrolidines / chemistry*
  • Quinones / chemistry*
  • Stereoisomerism
  • Vinyl Compounds / chemistry*

Substances

  • 1,4-dihydroquinone
  • Alkynes
  • Carbamates
  • Imines
  • Indoles
  • Ions
  • Pyrrolidines
  • Quinones
  • Vinyl Compounds
  • Ether
  • indoline
  • pyrrolidine