Substituted α-Alkylidene Cyclopentenones via the Intramolecular Reaction of Vinyl Cations with Alkenes
Authors:
- 24 December 2019
- journal article
- letter
- Published by American Chemical Society (ACS) in Organic Letters
- Vol. 22 (2) , 497-500
Abstract
Substituted α-alkylidene cyclopentenones are formed in up to 93% yield by the intramolecular capture of vinyl cations with pendent alkenes. An increased level of substitution at the β-position of the β-hydroxy-α-diazoketone starting material changed the course of the reaction to instead give a lactone product. A reaction path that involves bond reorganization via an acylium ion intermediate is proposed to explain these results. Substrate scope studies showed that more stable vinyl cations gave higher α-alkylidene cyclopentenone yields. This study provides a mild and efficient method to form α-alkylidene cyclopentenones that complements C–H insertion and Nazarov cyclization strategies.Keywords
Funding Information
- Division of Chemistry (CHE-1665113)
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