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Updated: May 6, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Potassium isopropoxide: for sulfination it is the only base you need!
Mahmoud Sayah1, Michael G Organ
1Department of Chemistry, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3 (Canada).
Abstract:
PEPPSI max: KOiPr has been identified as the key ingredient for Pd-catalyzed sulfination. Potassium is essential to keep the thiol concentration low, and isopropoxide is necessary for precatalyst activation and to break up Pd-sufide-based resting states. Together with the reactive Pd-PEPPSI-IPent(Cl) o-picoline catalyst, this system couples profoundly deactivated partners at RT that other catalysts cannot accomplish in refluxing toluene.
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