Catalytic, Asymmetric α‐Fluorination of Acid Chlorides: Dual Metal—Ketene Enolate Activation.

In this Communication, we disclose a catalytic, highly enantioselective (up to >99% ee) α-fluorination of acid chlorides to produce a variety of optically active carboxylic acid derivatives from readily accessible and commercially available starting materials. The reaction depends on dually activated ketene enolates generated from two discrete catalysts—a chiral nucleophile and an achiral transition metal complex working in tandem. The active, putative α-fluorobis(sulfonimide) intermediates readily transacylate in situ under mild conditions upon addition of a wide variety of nucleophiles, including complex natural products. As a consequence, the power of this method is witnessed by the broad range of α-fluorinated products that can be accessed efficiently depending on the work up conditions.