benzofurans and selectfluor

An efficient protocol was developed to access 3-fluoro-2-hydroxy-2-substituted benzo[b]furans with Selectfluor™ as the fluorinating reagent in MeCN and water. By utilizing SOCl2/Py as the dehydrating agent, the compounds above were readily converted to 3-fluorinated, 2-substituted benzo[b]furans in high yields.

Topics: Benzofurans; Diazonium Compounds; Hydrocarbons, Fluorinated; Molecular Structure

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.

Topics: Benzofurans; Carboxylic Acids; Catalysis; Diazonium Compounds; Halogenation; Hydrogen Bonding; Lactones; Magnetic Resonance Spectroscopy