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Updated: Jul 4, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Pd-catalyzed regio- and enantioselective allylation of cyclic allylboronates
Cheng Zhang1, Roman Popov1, Baptiste Leforestier1
1Department of Organic Chemistry, University of Geneva 30 Quai Ernest Ansermet Geneva 1211 Switzerland clement.mazet@unige.ch.
Abstract:
A robust protocol for the palladium-catalyzed regio- and enantioselective allylic substitution of 6-membered cyclic boronate salts is reported, enabling efficient access to complex scaffolds possessing two distinct alkenes, a synthetic boron handle, and an allylic tertiary stereocenter. This methodology is characterized by high levels of stereoselectivity and regioselectivity across a wide range of substrates. The synthetic potential of this approach has been demonstrated by several transition metal-catalyzed selective derivatizations. Computational studies at a mixed UMA/DFT level of theory reveal that the reaction is governed by a Curtin-Hammett scenario, wherein reductive elimination from hetero-bis-σ-allyl palladium(ii) intermediates constitutes the regio- and enantio-determining step of the process.
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