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Updated: Jun 26, 2026
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Enantioselective Carbonyl Crotylation of Alcohol Proelectrophiles via Ruthenium-Catalyzed Hydrogen Autotransfer:
Peyton W Meares1, Catherine G Santana1, Michael J Krische1
1University of Texas at Austin, Department of Chemistry, 105 E 24th St. Austin, TX 78712, USA.
Abstract:
From the first report of 1,3-butadiene-mediated carbonyl crotylation in 2008 to the recent development of a simple ruthenium-JOSIPHOS catalyst derived from inexpensive, air-stable RuHCl(CO)(PPh3)3, the discovery and evolution of 1,3-butadiene-mediated carbonyl crotylation is reviewed. The key role of iodide counterions in guiding metal-centered stereogenicity and, therefrom, regio-, stereo- and site-selectivity is highlighted, as are applications in polyketide total synthesis. These methods are unique in their ability to affect crotylation of primary alcohol proelectrophiles in the presence of free secondary hydroxyl groups and offer an atom-efficient alternative to classical protocols for aldehyde crotylations that rely on premetalated reagents.
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