One-Pot Enol Silane Formation–Allylation of Ketones Promoted by Trimethylsilyl Trifluoromethanesulfonate

In memory of Professor David A. Evans

Abstract

Ketones and related substrate classes undergo enol silane formation in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and triethylamine, reaction conditions that also promote the in situ ionization of allyl propionates. When these two processes are performed in one pot, allylation of the ketone is observed in high yields. Aldehydes, esters, and thioesters also serve as enol silane precursors under these conditions. When unsymmetrical allyl cations are employed, regioselectivity depends upon the electronic and steric properties of the substituents.

Key words

allylation - enol silane - one pot - alkylation - silyl triflates - Lewis acid catalysis - regioselectivity

Publication History

Received: 22 July 2022

Accepted after revision: 12 October 2022

Accepted Manuscript online:
12 October 2022

Article published online:
05 December 2022

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