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Updated: Mar 31, 2026
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Gold-Catalyzed Ammonium Acetate Assisted Cascade Cyclization of 2-Alkynylarylketones
Maciej E Domaradzki1, Yuhua Long1, Zhigang She1
1Department of Chemistry and Biochemistry, Queens College and the Graduate Center of the City University of New York , 65-30 Kissena Boulevard, Flushing, New York 11367, United States.
Abstract:
An ammonium acetate assisted gold-catalyzed cascade cyclization reaction of 2-alkynylarylketones is described. Under the reported conditions, a gold-catalyzed intramolecular cyclization of 2-alkynylarylketones takes place through two competing reaction mechanisms-a 5-exo-dig or a 6-endo-dig cyclization-leading to two regioisomeric intermediates: isobenzofuranium or isobenzopyrylium. In the presence of ammonium acetate, the two intermediate compounds undergo further rearrangement to 2,3-disubstituted indenones and 1,3-disubstituted isoquinolines, respectively. While both reaction pathways proceed via a cyclization-rearrangement cascade, the gold-mediated 5-exo-dig process is especially notable, as it provides a novel cyclization protocol of 2-alkynylarylketones.
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