[formula: see text] Highly stereoselective formal [3 + 3] cycloaddition reactions of chiral vinylogous amides with alpha, beta-unsaturated iminiums are described. A mechanistic model is proposed to rationalize the observed stereoselectivity. The 6 pi-electron electrocyclic ring closure appears to be reversible, and a preferred rotation of the alkenyl group, one of the three 2 pi-components, during the ring closure step provides the thermodynamically favored diastereomer as the major product.
Highly Stereoselective Formal [3 + 3] Cycloaddition Reactions of Chiral Vinylogous Amides with α,β-Unsaturated Iminiums. -Vinylogous amides bearing a chiral side chain undergo a formal [3+3] cycloaddition. N-Heterocycles are formed under optimized conditions A) with moderate to good diastereoselectivity. -(SKLENICKA, HEATHER M.; HSUNG, RICHARD P.; WEI, LIN-LI; MCLAUGHLIN, MICHAEL J.; GERASYUTO, ALEKSEY I.; DEGEN, SHANE
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.