Catalytic Stereoselective Intermolecular Fluoroacylation of Unactivated Alkynes via C-F Bond Reconstruction
Tanmay Kanji1, Asma A Alharthi2,3, Abdulrahman H Husayni2,4
1Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Translational Research Hub, CardiffCF24 4HQ, United Kingdom.
Abstract:
Herein, we report a transition metal-free synthesis of monofluoroalkenes via a C-F bond reconstruction approach. The process employs inexpensive BF3·Et2O as a catalyst for the stereoselective intermolecular fluoroacylation of unactivated alkynes with alkyl/aryl acid fluorides to access various monofluoroalkene products (24 examples, typically >98:<2 Z:E). The synthetic utility of the products was demonstrated via their conversion into various heterocycles (pyrazoles, isoxazoles, and pyrimidines) and fluoroalkene-containing esters/amides.
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