Hydrochloric Acid → HCID 59609876, compound

Participants

Reaction Steps

4-Butoxy-(2,3-difluorophenyl)cyclohexene (24) (11.0 g) and THF (200 ml) were put in a reaction vessel under a nitrogen atmosphere, and cooled to −74° C. sec-Butyllithium (1.00 M, in a n-hexane and cyclohexane solution; 50.0 ml) was added dropwise thereto in the temperature range of −74° C. to −70° C., and the mixture was stirred for another 2 hours. Then, trimethyl borate (5.2 g) in a THF (50 ml) solution was added dropwise thereto in the temperature range of −74° C. to −65° C., and the stirring was continued for another 8 hours while the mixture was allowed to return to 25° C. Then, the reaction mixture was poured into a vessel containing 1N-hydrochloric acid (100 ml) and ice-water (500 ml), and mixed. Then, ethyl acetate (300 ml) was added thereto and the mixture was allowed to be separated into organic and aqueous phases, and extraction into an organic phase was carried out. The obtained organic layer was fractionated, washed sequentially with water, a saturated aqueous solution of sodium bicarbonate and brine, and then dried over anhydrous magnesium sulfate. Then, the solvent was distilled off under reduced pressure, giving 10.7 g of 4-(4-butoxycyclohexenyl)-2,3-difluorophenylboronic acid (25). The yield based on the compound (24) was 83.6%.

Provenance & Evidence