In conclusion, we discovered a new reaction of calciumbased heavy Grignard reagents, which were in-situ generated by a simple mechanochemical method, with unactivated alkyl fluorides in the absence of transition metal catalysts, providing the corresponding C(sp 3 )-F bond arylation products in moderate to good yields. Notably, this is the first example of nucleophilic substitution of an inert C(sp 3 )-F bond by organocalcium species. Preliminary theoretical calculations were used to elucidate the unprecedented reactivity of organocalcium nucleophiles toward activation of an inert C(sp 3 )-F bond. The present study suggests that our operationally simple mechanochemical protocol for rapidly generating organocalcium nucleophiles using commercial, unactivated calcium metal will provide a platform for discovering new reactions that are feasible only by calciumbased carbon nucleophiles.