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Updated: Jul 4, 2025

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Reactivity of Enyne-Allenes Generated via an Alder-Ene Reaction
Duy-Viet Vo1, Siyuan Su1, Rajdip Karmakar1
1Department of Chemistry, University of Illinois─Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States.
Abstract:
Tandem transformations of 1,3-diynyl propiolate derivatives are described. The Alder-ene reaction generates an enyne-allene, which undergoes a formal 1,7-H shift or a Diels-Alder reaction, depending on the substituent on the alkyne. A terminal or aryl-substituted alkyne promotes a 1,7-H shift to generate a new enyne-allene, which undergoes a Myers-Saito cycloaromatization followed by a 1,5-H transfer-mediated cyclization to form highly functionalized benzo-fused 6-membered cycles. The reactivity of the preformed enyne-allene shows comparable reactivity profiles.
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