One-Pot Enol Silane Formation-Alkylation of Ketones with Propargyl Carboxylates Promoted by Trimethylsilyl Trifluoromethanesulfonate
Ketones readily undergo conversion to enol silanes in the presence of trialkylamine base and trimethylsilyl trifluoromethanesulfonate (TMSOTf) and add to propargyl cations to yield b-alkynyl ketones. The propargyl cations are generated in the same reaction flask through the TMSOTf-promoted ionization of propargyl acetates or propargyl propionates. A range of enol silane precursors and propargyl carboxylates reacts efficiently (20 examples, up to 99% yield). Cyclization of a representative product in the presence of TMSOTf provided 61% yield of the trisubstituted furan.
Copyright © 2018, Journal of Organic Chemistry.
C. Wade Downey, Danielle N. Confair,* Yiqi Liu,* Elizabeth D. Heafner.* One-Pot Enol Silane Formation-Alkylation of Ketones with Propargyl Carboxylates Promoted by Trimethylsilyl Trifluoromethanesulfonate. Journal of Organic Chemistry 2018, 83, 12931- 12938.