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Published on: June 21, 2017
Oxidopyrylium-Alkene [5 + 2] Cycloaddition Conjugate Addition Cascade (C3) Sequences: Scope, Limitation, and
Riley H Kaufman1, Chunyin M Law1, Justin A Simanis1
1Department of Chemistry , Illinois State University , Campus Box 4160 , Normal , Illinois 61790-4160 , United States.
Abstract:
Oxidopyrylium-alkene [5 + 2] cycloaddition conjugate addition cascade (C3) sequences are described. Intramolecular cycloadditions involving terminal alkenes, enals, and enones were investigated. Substrates with tethers of varying lengths delivered five- and six-membered carbocycles and heterocycles thus demonstrating the scope and limitation of the cycloaddition-conjugate addition cascade. Several experiments and theoretical calculations provide evidence for the proposed mechanistic pathway.
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