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Synthesis of α-heterosubstituted ketones through sulfur mediated difunctionalization of internal alkynes
Zhong Zhang1, Yuzheng Luo1, Hongguang Du1
1State Key Laboratory of Chemical Resource Engineering , Department of Organic Chemistry , Faculty of Science , Beijing University of Chemical Technology , Beijing 100029 , China . Email: dhg@mail.buct.edu.cn ; Email: jxxu@mail.buct.edu.cn ;
Abstract:
Synthesis of α-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 α-sulfonium ketone, and then substitution with various nucleophiles. This method provides a unified route to access α-amino ketones, α-acyloxy ketones, α-thio ketones, α-halo ketones, α-hydroxy ketones, and related heterocyclic structures, in a rapid fashion.
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