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Updated: May 9, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Studies toward the generation of functionalized quaternary carbon centers relying on Wittig and Wittig-Still allylic
Stephen Hanessian1, Stéphane Dorich, Amit Kumar Chattopadhyay
1Department of Chemistry, Université de Montréal, Station Centre-Ville, C.P. 6128, Montreal, Qc, H3C 3J7, Canada. stephen.hanessian@umontreal.ca
Abstract:
Although the [2,3]-Wittig and Wittig-Still rearrangements have long been known, their application in the generation of quaternary carbon centers in carbocyclic ring systems is sparse. Model studies utilizing this strategy and possible mechanisms are discussed herein. Unprecedented examples of an α-elimination pathway from stannylmethyl allyl ethers as a major undesired product in some Wittig-Still rearrangements are reported.
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