5-BROMO-2-METHOXY-PYRIDIN-N-OXIDE synthesis

Yield:446284-14-6 57.1%

Reaction Conditions:

with 3-chloro-benzenecarboperoxoic acid in dichloromethane at 40; for 16 h;Inert atmosphere;

Steps:

D.1 Step 1: preparation of 5-Bromo-2-methoxypyridine 1-oxide (2D):

Step 1: preparation of 5-Bromo-2-methoxypyridine 1-oxide (2D): To a stirred solution of 5-bromo-2-methoxypyridine ID (22.6 g, 120.2 mmol) in DCM (120 mL) was added m-CPBA (82.7 g, 480.8 mmol) in two portions. The reaction mixture was stirred at 40°C for 16 h. After the mixture was cooled to rt, and the precipitate was filtered. The filtrate was washed with aqueous Na₂S₂0₃, followed by aqueous Na₂C0₃. The organic layer was concentrated and purified directly by column chromatography (MeOH : DCM= 10:1) to give the product as white solid (14 g, 57.1%).

References:

WO2013/113669,2013,A1 Location in patent:Page/Page column 74