Direct arylation of alkyl fluorides using in situ mechanochemically generated calcium-based heavy Grignard reagents†

Here, we report the reaction of calcium-based heavy Grignard reagents, which are easily generated by a mechanochemical method, with unactivated alkyl fluorides in the absence of transition metal catalysts to produce the corresponding arylated products in moderate to good yields. This is the first example of the nucleophilic substitution of an inert C(sp³)–F bond by an organocalcium species. Preliminary mechanistic studies based on theoretical calculations indicate that tetrameric aryl calcium species facilitate the unprecedented C(sp³)–F bond arylation.