Synthesis of α-heterosubstituted ketones through sulfur mediated difunctionalization of internal alkynes

Synthesis of a-heterosubstituted ketones was achieved through sulfur mediated difunctionalization of internal alkynes in one pot. The reaction design involves: phenyl substituted internal alkyne attacking triflic anhydride activated diphenyl sulfoxide to give a sulfonium vinyl triflate intermediate, hydrolysis to give an a-sulfonium ketone, and then substitution with various nucleophiles. This method provides a unified route to access a-amino ketones, a-acyloxy ketones, a-thio ketones, a-halo ketones, ahydroxy ketones, and related heterocyclic structures, in a rapid fashion.