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Updated: Aug 30, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Cross-coupling of alkynylsilanols with aryl halides promoted by potassium trimethylsilanolate
Scott E Denmark1, Steven A Tymonko
1Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, IL 61801, USA. denmark@scs.uiuc.edu
Abstract:
The palladium-catalyzed cross-coupling of aliphatic alkynylsilanols with aryl iodides has been demonstrated with potassium trimethylsilanolate as the coupling promoter and copper(I) iodide as a cocatalyst. The cross-coupling proceeds at room temperature in good to excellent yield with a range of aryl iodides. A comparison of the reactivity of alkynylsilanols, trimethylsilylalkynes, and terminal alkynes under fluoride and fluoride-free conditions was performed to elucidate the role of silicon in the Sonogashira reaction.
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