Base-Catalyzed Stereoselective Vinylation of Ketones with Arylacetylenes: A New C(sp3)C(sp2) Bond-Forming Reaction

Alkylaryl‐ and alkylheteroarylketones, including those with condensed aromatic moieties, are readily vinylated with arylacetylenes (KOH/DMSO, 100 °C, 1 h) to give regio‐ and stereoselectively the (E)‐β‐γ‐ethylenic ketones ((E)‐3‐buten‐1‐ones) in 61–84 % yields and with approximately 100 % stereoselectivity. This vinylation represents a new C(sp3)C(sp2) bond‐forming reaction of high synthetic potential. A valuable vinylation! Previously unknown C‐vinylation of ketones occurs with high E stereoselectivity and excellent yields when alkylaryl‐ and alkylheteroarylketones are treated with arylacetylenes in the presence of KOH/DMSO at 100 °C. This represents a new C(sp3)C(sp2) bond‐forming reaction of wide scope (see scheme).