Esters as Alkynyl Acyl Ammonium and Azolium Precursors: A Formal [2 + 3] Annulation with Amidomalonates via Lewis Base/Lewis Acid Cooperative Catalysis

Org Lett. 2017 Dec 15;19(24):6724-6727. doi: 10.1021/acs.orglett.7b03453. Epub 2017 Dec 1.

Abstract

Esters are for the first time used as α,β-unsaturated alkynyl acyl ammonium and azolium precursors to undergo a formal [2 + 3] annulation with amidomalonates through DMAP/LiCl or carbene/LiCl cooperative catalysis. A wide range of (Z)-5-amino-3-furanones were obtained in moderate to high yields with high regioselectivity and stereoselectivity. In addition, a plausible mechanism based on the calculated charge distribution of the intermediates is proposed to explain the regioselectivity.

Publication types

  • Research Support, Non-U.S. Gov't