We report the first successful example of a highly enantioselective fluorolactonization with an electrophilic fluorinating reagent, Selectfluor(®), in the presence of a novel bifunctional organocatalyst. The catalyst design includes a carboxylate anion functioning as a phase-transfer agent and a benzyl alcohol unit to capture the substrate through hydrogen bonding. Fluorinated isobenzofuranones were obtained in good yields with up to 94% ee (97:3 er). On the basis of mechanistic studies, we propose a unique reaction mechanism with potential for further applications.

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Asymmetric Fluorolactonization with a Bifunctional Hydroxyl Carboxylate Catalyst. -A highly enantioselective fluorolactonization of ortho-vinylbenzoic acids with Selectfluor and a bifunctional phase-transfer organocatalyst provides (fluoromethyl)isobenzofuranones. -(EGAMI, H.; ASADA, J.; SATO, K.; HASHIZUME, D.; KAWATO, Y.; HAMASHIMA*, Y.; J. Am. Chem. Soc. 137 (2015) 32, 10132-10135, http://dx.doi.org/10.1021/jacs.5b06546 ; Sch. Pharm. Sci., Univ. Shizuoka, Suruga, Shizuoka 422, Japan; Eng.) -T. Stabingis 06-135