Hydrochloric Acid → 5-Formylfuran-2-boronic acid

Participants

Reaction Conditions

Reaction Steps

An amount of 1.0 g (4.1 mmol) of 4-bromo-2-(diethoxymethyl)furan, is dissolved in ether (15 mL) and cooled to −78° C. To this is added 4.3 mL (6.02 mmol) of sec-butyllithium. After stirring at −78° C. for 30 minutes, triisopropyl borate (1.10 mL, 5.01 mmol) is added dropwise. The mixture is stirred at −78° C. for 1.5 hours and brought to room temperature for 2 hours. The mixture is hydrolyzed with 2N HCl and stirred at room temperature for 1 hour. The ether layer is separated and the water layer is washed once more with ether. The combined ether layers is washed once with brine and dried with sodium sulfate. Evaporated to give 563 mg of the boronic acid as dark oil.

Provenance & Evidence