反应 #893

反应方程式

4,5-Dibromo-2-methyl-3(2H)-pyridazinone

sodium methoxide

→

desired product

4-Bromo-5-methoxy-2-methyl-3(2H)-pyridazinone

溶剂

methanol

methanol

反应条件

后处理

1. 1
   其他The ice bath was removed
2. 2
   其他The methanol was removed by evaporation at reduced pressure
3. 3
   其他The residue was partitioned between dichloromethane and water
4. 4
   干燥The organic layer was dried over magnesium sulfate
5. 5
   浓缩concentrated

实验过程

4,5-Dibromo-2-methyl-3(2H)-pyridazinone (20 g, Maybridge Chemical Company) was cooled in an ice bath and treated successively with methanol (200 mL) and sodium methoxide (12 mL of a 30% solution in methanol). The ice bath was removed and the reaction was allowed to stir at 23° C. for 3 h. The methanol was removed by evaporation at reduced pressure. The residue was partitioned between dichloromethane and water. The organic layer was dried over magnesium sulfate and concentrated to provide the desired product 17 g as a whim solid melting at 146°-147° C. 1 H NMR (CDCl3): 7.7 (1H), 4.0 (3H), 3.8 (3H).

来源