反应详情

温度

70 °C

A suspension of 2-methyloxazolo 5,4-b!pyridine-5,6-dicarboxylic acid (4.84 g, 0.0218 mol) in acetic anhydride (150 mL) is slowly heated to 70° C. at which point all the solids dissolve forming a yellow solution. The reaction mixture is heated at 70° C. overnight, cooled to room temperature, and concentrated in vacuo. Xylene is added to remove excess acetic anhydride by codistillation. 2-Methyloxazolo 5,4-b!pyridine-5,6-dicarboxylic anhydride is obtained as a pale yellow solid in 97% yield melting point 194°-196° C.

1. additionA suspension of 2-methyloxazolo 5,4-b
2. dissolutiondissolve
3. customforming a yellow solution
4. temperaturecooled to room temperature
5. concentrationconcentrated in vacuo
6. additionXylene is added
7. customto remove excess acetic anhydride by codistillation