Реакция #893

Уравнение реакции

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

sodium methoxide

→

desired product

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

Растворители

methanol

methanol

Условия реакции

Обработка

1. 1
   ДругоеThe ice bath was removed
2. 2
   ДругоеThe methanol was removed by evaporation at reduced pressure
3. 3
   ДругоеThe residue was partitioned between dichloromethane and water
4. 4
   СушкаThe organic layer was dried over magnesium sulfate
5. 5
   Концентрированиеconcentrated

Методика

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).

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