Реакция #52990

Уравнение реакции

4-Amino-2,6-dichlorobenzoic acid methyl ester

NaNO2

HBr

→

4-bromo-2,6-dichlorobenzoic acid methyl ester

Растворители

water

Условия реакции

Обработка

1. 1
   Температураthe mixture was warmed up to 100° C
2. 2
   workup.STIRRINGThe mixture was then stirred at 100° C. for 30 min
3. 3
   Экстракцияextracted with AcOEt
4. 4
   СушкаThe extract was dried (MgSO4)
5. 5
   Фильтрацияfiltered
6. 6
   Другоеevaporated
7. 7
   ДругоеThe residue was purified by column chromatography (silica gel; eluent: hexane and AcOEt 50:1)

Методика

4-Amino-2,6-dichlorobenzoic acid methyl ester (1.00 g) was suspended in 40% aq. HBr and the mixture was cooled lto 0-5° C. After NaNO2 (376 mg) was added in small portions, the mixture was stirred for about 5 min. Copper (100 mg) was added and the mixture was warmed up to 100° C. The mixture was then stirred at 100° C. for 30 min, diluted with water and extracted with AcOEt. The extract was dried (MgSO4), filtered and evaporated. The residue was purified by column chromatography (silica gel; eluent: hexane and AcOEt 50:1) to give 4-bromo-2,6-dichlorobenzoic acid methyl ester (1.07 g).

Источник