Silyl Radical‐Promoted Defluorination of Fluoroalkyl Ketones to Access Fluorinated 1,3‐Dienes†

Comprehensive Summary Herein, we report a base‐promoted, silylborane‐mediated strategy for the transformation of fluorinated carbenes derived from fluoroalkyl ketones, enabling the efficient and stereoselective synthesis of diverse fluorinated 1,3‐dienes and alkenes. This metal‐free protocol exhibits broad functional group tolerance, accommodating halogens, heteroarenes, and various perfluoroalkyl groups, providing streamlined access to fluorinated frameworks that are otherwise challenging to obtain using conventional methods. Mechanistic studies support a silyl radical‐initiated pathway, wherein t ‐BuONa promotes the in‐situ generation of silyl radicals that abstract allylic C–H bonds, triggering downstream selective defluorination. This work establishes a practical platform for the synthesis of valuable fluorinated building blocks and offers insights into silyl radical‐driven transformations under metal‐free conditions.