Hydrochloric Acid → (2,2-dimethyl-2H-chromen-6-yl)boronic acid

Participants

Reaction Steps

To a solution of 6-bromo-2,2-dimethyl-2H-chromene (18 g) in tetrahydrofuran (150 mL) was added butyllithium (53 mL, 1.6 M hexane solution) at −78° C. under an argon atmosphere, and the mixture was stirred for 30 min. Triisopropyl borate (21 mL) was added, and the mixture was stirred for 3 hr while allowing to warm to room temperature. 1 M hydrochloric acid (150 mL) was added to the reaction mixture, and the mixture was stirred for 2 hr and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate, and the solvent was evaporated. The residue was purified by silica gel column chromatography to give the title compound (13 g, 82%) as colorless crystals.

Provenance & Evidence