Reaction #2146683

Reaction equation

sodium methoxide methanol

2-bromo-3-hydroxypyridine

methyl iodide

→

2-bromo-3-methoxypyridine

Solvents

dimethylsulfoxide

Conditions

Workup

1. 1
   workup.DISTILLATIONto distill off methanol
2. 2
   TemperatureAfter the reaction solution was cooled down to 10° C.
3. 3
   OtherAfter the completion of the reaction
4. 4
   Extractionextracted twice with chloroform
5. 5
   WashThe combined chloroform layer was washed with a 1 mol/L sodium hydroxide solution
6. 6
   Washwashed twice with a saturated sodium chloride solution
7. 7
   Dryingdried over anhydrous sodium sulfate
8. 8
   workup.DISTILLATIONAfter the solvent was distilled off under reduced pressure

Procedure

100.0 g (corresponding to 0.575 mol) of 2-bromo-3-hydroxypyridine was dissolved in 310 mL of dimethylsulfoxide, and 575 mL (corresponding to 0.575 mol) of a 1 mol/L sodium methoxide-methanol solution was added thereto. Then, the reaction solution was heated to 90° C. to distill off methanol. After the reaction solution was cooled down to 10° C. or lower, 93.9 g (corresponding to 0.662 mol) of methyl iodide was added, and then stirred at room temperature for 20.5 hours. After the completion of the reaction, the reaction solution was poured into ice water and extracted twice with chloroform. The combined chloroform layer was washed with a 1 mol/L sodium hydroxide solution, washed twice with a saturated sodium chloride solution, and dried over anhydrous sodium sulfate. After the solvent was distilled off under reduced pressure, 65.4 g (corresponding to 0.348 mol) of 2-bromo-3-methoxypyridine was obtained (FIG. 2, Step 1).

Source