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Updated: Aug 24, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Metal-Free Disulfonylation of Terminal Allenes
Suyu Ji1, Xiyang Cao1, Zhiguo Zhang1
1Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, 46 East of Construction Road, Xinxiang, Henan453007, China.
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A facile and efficient metal-free protocol for the highly regio- and stereoselective disulfonylation of terminal allenes has been established herein, which enables the straightforward synthesis of structurally diverse (E)-1,2-disulfonyl allylic derivatives in satisfactory yields. This synthetic transformation proceeds smoothly via homodifunctionalization of terminal allenes by utilizing a base combined with 1,10-phenanthroline (Phen) as a dual-promoting system. The developed thermally driven methodology features mild operational conditions and good functional group compatibility. This practical synthetic strategy provides a reliable and versatile platform for the construction of allylic bis-sulfone skeletons.
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