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Updated: Jan 6, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Sc(III)-Catalyzed Carbonyl-Yne Reaction for the Diastereoselective Allene Synthesis: A Concerted Asynchronous
Xinya Yuan1, Jiashen Yang1, Shaozhong Wang1
1State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Engineering Research Center of Photoresist Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, China.
None:
The carbonyl-yne reaction, involving propargylic C-H bond cleavage for carbon-carbon bond formation, is significantly less developed than the classical Alder-ene reaction due to the linear geometry and relatively weak nucleophilicity of alkynes compared to alkenes. Herein, we report a Sc(OTf)3-catalyzed carbonyl-yne reaction enabling the diastereoselective synthesis of multisubstituted allenes from α-ketoamide-tethered alkynes with 100% atom economy and excellent diastereoselectivity (up to 20/1 dr). DFT calculations support a concerted, asynchronous mechanism involving C-C bond formation and propargylic C-H cleavage. Theoretical analysis suggests that the observed stereoselectivity arises from an interplay of electronic and entropic effects in the transition states.
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