Hydrochloric Acid → [2-Methoxy-3-(trifluoromethyl)phenyl]boronic acid

Participants

Reaction Steps

To a solution of 1-methoxy-2-(trifluoromethyl)benzene (6.30 g, 35.8 mmol) in THF (150 mL) was added n-BuLi (21.0 ml, 2.50 M hexane solution, 53.7 mmol), and the mixture was stirred at room temperature for 1 hr. The solution was cooled to −78° C., tris(1-methylethyl)borate (8.08 g, 43.0 mmol) was added, and the mixture was stirred at −78° C. for 0.5 hr. The reaction solution was allowed to cool to room temperature and stirred for 16 hr. The mixture was acidified with 1M hydrochloric acid and extracted with ethyl acetate (300 mL). The extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give a mixture (6.52 g, yield 83%) of [2-methoxy-3-(trifluoromethyl)phenyl]boronic acid and [3-methoxy-2-(trifluoromethyl)phenyl]boronic acid.

Provenance & Evidence