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Updated: Jul 7, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
A new two-step four-component synthesis of highly functionalized cyclohexenols by sequential nickel-catalyzed
Mario Lozanov1, John Montgomery
1Department of Chemistry, Wayne State University, Detroit, Michigan 48202-3489, USA.
Abstract:
A new two-step procedure for the synthesis of cyclohexenols has been developed. A nickel-catalyzed three-component addition of an enal, alkyne, and acetylenic tin affords substituted hept-4-en-6-ynals. The products of this first step then undergo a second nickel-catalyzed reaction with organozincs or organoboranes to afford densely functionalized cyclohexenols. Variation in each of the four components is tolerated to provide access to a wide range of versatile building blocks.
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