反応 #893

反応方程式

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

sodium methoxide

→

desired product

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

溶媒

methanol

methanol

反応条件

後処理

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

実験手順

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).

出典