Tributyl borate → (4-Bromo-5-methylthiophen-2-yl)boronic acid

Participants

Reaction Steps

n-Butyl lithium in hexane is added to a stirred solution of compound 2 in dry ether (150 mL) at −78° C. under argon atmosphere. After stirring for 30 min, boric acid tri-butyl ester is quickly added to the reaction mixture. The mixture is extracted with 4% aq. NaOH (100 mL), the extract is collected and neutralized by with 10% HCl. The solid residue is washed, filtrated, and dried. Compound 3 is obtained as a yellowish solid. M.p. 229° C.

Provenance & Evidence