A metal-free tandem cycloaddition strategy for the synthesis of indolizines from pyridine derivatives and γ-bromo-crotonates under mild conditions

Abstract

A one-pot synthetic protocol involving 1,3-dipolar cycloaddition/deprotonation/elimination/oxidation for the construction of indolizines has been proposed from easily available pyridine derivatives and γ-bromo-crotonates via a metal-free tandem process. A variety of indolizine derivatives were synthesized under mild conditions. Noteworthy features of this synthetic strategy are short reaction time, using air as oxidant and mild reaction conditions.