Regioselective Synthesis of Poly-Substituted Pyrroles from Baylis-Hillman Adducts via the[3+1+N]Annulation Strategy

摘要

Poly-substituted pyrrole derivatives were synthesized from Baylis-Hillman adducts via the following consecutive reactions comprised of(i)bromination of the Baylis-Hillman adduct,(ii)In-mediated Barbier reaction with aldehyde,(iii)PCC oxidation to alpha-methylene-gamma-keto ester,(iv)reaction with amine to form enamine intermediate,(v)Michael type cyclization,and the final(vi)aerobic oxidation.