Hydrochloric Acid → 2,3-Methylenedioxyphenyl boronic acid

Participants

Reaction Steps

nBuLi (2.5M in hexanes, 2.38 mL, 5.97 mmol) was dropwise added to a solution of 4-bromo-1,3-benzodioxole (1 g, 4.97 mmol) and triisopropyl borate (1.49 mL, 6.47 mmol) in 50 mL of dry tetrahydrofuran at −78° C. under argon. The reaction was maintained at that temperature for 3 hours, then warmed up to room temperature and cooled back to 0° C. immediately. The solution was acidified to pH=2 with HCl 2N and neutralized to pH=7 with NaOH 2N, it was then extracted with ethyl acetate (3×25 ml), the organic solution was washed with brine, dried over sodium sulphate and the solvent removed under reduced pressure to yield the title compound (570 mg, 69%) as a white solid.

Provenance & Evidence