Regioselective Dicarbofunctionalization and Cyclization Diversity of Unsymmetrical Alkynes

Presented in this talk will be work in the discovery of a regio- and stereoselective syn-1,2-dicarbofuctionalization of unsymmetrical internal alkynes. A Pd-catalyzed three-component coupling of aryl diazonium salts/halides (electrophile) and aryl boronic acids (or olefins)/methyl boronic acids (nucleophile) with unsymmetrical alkynes enables access to tetra-substituted unsymmetrical olefins. A Brønsted acid mediated cyclization diversity of yne-tethered-ynamide is also discussed. A serendipitous observation where the reactivity of simple alkynes exceeds that of ynamides is also discussed. Thus, a unique sulfur‐radical‐triggered cyclization of yne‐tethered ynamides, which involves attack of the alkyne by a thiyl radical followed by cyclization with the ynamide.