86467-39-2

General procedure for the synthesis of 2-methyloxazolo[4,5-B]pyridine from 2-amino-3-hydroxypyridine and triethyl orthoacetate: 80 mL of triethyl orthoacetate was added to 15 g (136 mmol) of 2-amino-3-hydroxypyridine, followed by the addition of a catalytic amount of p-toluenesulfonic acid. The reaction mixture was stirred at 120 °C for 4 hours. After completion of the reaction, the reaction mixture was cooled and triethylamine was added to neutralize p-toluenesulfonic acid in the reaction system. Subsequently, the solvent was removed by distillation under reduced pressure using a rotary evaporator. The crude product was purified by silica gel column chromatography to afford 12.0 g of the target product 2-methyloxazolo[4,5-B]pyridine in 65.8% yield.

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