Triisopropyl borate → 3-Cyano-4-fluorophenylboronic acid

Participants

Reaction Conditions

Reaction Steps

A solution of n-butyllithium (5.6 ml, 2.5M in hexanes) was added over a 20 minute period to a solution of 5-bromo-2-fluorobenzonitrile and triisopropylborate (3.46 ml) in tetrahydrofuran (10 ml) at −78° C. The resulting solution was stirred at −78° C. for 30 minutes and then quenched by the addition of a 2M hydrochloric acid (20 ml) and extracted into ethyl acetate. The combined extracts were dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by trituration using diethyl ether: hexane 1:2 to afford the sub-title compound as a solid (1.24 g).

Provenance & Evidence