An efficient method for the synthesis of polysubstitutedi ndolizinesh as been developed based on formal [4+ +2] annulation of 1-acetylaryl2 -formylpyrroles with enals, followed by oxidative aromatization. Pyridinetype six-membered rings were constructed in this transformation. This transition metal-free reactionf eatures mild reaction conditions, ab road substrate scope, and excellent functional group tolerance. Notably,t he formyl group is welltoleratedu nder reaction conditions. Scheme1.Representative examples and synthetic methodsfor indolizines.[a] M. Gong, J.Supporting information and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

N-Heterocyclic carbenes-catalyzed [3+3] annulation of bromoenals with 2-aminochromones has been successfully developed. A structurally diverse set of Chromeno[2,3-b]pyridinones was efficiently constructed in acceptable to excellent yields. The reaction features mild...