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 メ-methylene-ャ-keto ester, (iv) reaction with amine to form enamine intermediate, (v) Michael type cyclization, and the final (vi) aerobic oxidation.