Trimethyl borate → (5-(Methoxymethyl)pyridin-3-yl)boronic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of n-butyl lithium in hexane (6 ml of a 1.6M solution) in diethyl ether (40 ml) at -100° C. under nitrogen was added dropwise 3-bromo-5-methoxymethylpyridine (1.2 g, 6 mmol) (WO 95/28400) in diethyl ether (20 ml). After stirring for 45 minutes at -100° C., trimethyl borate (1.1 ml, 9.8 mmol) was added and the reaction mixture stirred at -100° C. for an extra 75 minutes. Water was added followed by 4N aqueous sodium hydroxide when the temperature reached 10° C. The aqueous layer was decanted, acidified to pH 5 with 2N aqueous hydrochloric acid and extracted 5 times with dichloromethane. The combined organics were dried (sodium sulphate) and evaporated to give the title compound as an oil (100 mg, 10%). MS, m/z 168 for (M+H)+. Rf 0.05 in ammonia/methanol/dichloromethane (1/10/90) on silica plate.

Provenance & Evidence