One-Pot Sequential Catalytic Hydration of Alkynes and α-Alkylation with Alcohols for the Synthesis of α-Alkylated Ketones

A strategy for the synthesis of alpha-alkylated ketones via one-pot, sequential, catalytic hydration of alkynes and alpha-alkylation with alcohols was proposed and successfully accomplished. In the presence of chloro[1,3-bis(2,6-diisopropylphenyl) imidazol-2-ylidene] gold(I) ([(IPr) AuCl])/silver triflate (AgOTf) and water, a series of alkynes are first hydrated to give the corresponding methyl ketones, which in turn are alpha-alkylated by adding pentamethylcyclopentadienyliridium-(III) chloride ([Cp*IrCl2](2))/KOtBu and alcohols to the reaction mixture. Notably, this reaction is highly attractive because of easily available starting materials, high atom efficiency, good to excellent yields, and minimal consumption of chemicals and energy. The present research will also facilitate the development of one-pot, sequential, catalytic reactions based on hydrogen autotransfer (or hydrogen-borrowing) processes.