Intermolecular polar [4π++ 2π] cycloadditions of cationic 2-azabutadienes from thiomethylamines: a new and efficient method for the regio- and diastereo-selective synthesis of 1,2,3,4-tetrahydroquinolines

Abstract

Substituted 1,2,3,4-tetrahydioquinolines and related condensed nitrogen-heterocycles are formed highly regio- and diastereo-selectively with yields ranging from 57 to 100% by intermolecular polar [4π⁺+ 2π] cycloadditions of cationic 2-azabutadienes from thiomethylamines and various dienophiles.