Hydrochloric Acid → HCID 66966679, compound

Participants

Reaction Conditions

Reaction Steps

4-Bromo-2,3′,4′,5′-tetrafluoro-1,1′-biphenyl (T-39) (12.0 g) and diethyl ether (220 ml) were put into a reaction vessel under a nitrogen atmosphere and cooled to −74° C. 1.57M of n-butyl lithium in n-hexane solution (31.5 ml) was added dropwise thereto in the temperature range of −74° C. to −68° C. and stirred another 120 minutes. Then, trimethyl borate (6.70 ml) in THF (20 ml) solution was added dropwise in the temperature range of −75° C. to −68° C. and the stirring was continued for another 180 minutes while the reaction mixture was allowed to come to 25° C. Then, the reaction mixture was cooled to −30° C. and 6N-hydrochloric acid (40 ml) was slowly added dropwise thereto, and the mixture was stirred for another 180 minutes. After the reaction thus obtained had been allowed to come to 25° C., it was poured into ice-water (200 ml) and mixed. Organic and aqueous layers were separated by adding ethyl acetate 200 ml). The aqueous layer was extracted with toluene. The organic layers combined were washed sequentially with water, a saturated aqueous solution of sodium hydrogencarbonate and brine, and dried over anhydrous magnesium sulfate. Then, the solvent was distilled off under reduced pressure and 2,3′,4′,5′-tetrafluoro-1,1′-biphenylboronic acid (T-40) (8.91 g) was obtained. The yield based on the compound (T-39) was 85%.

Provenance & Evidence