Реакция #994889

Уравнение реакции

HCl

isoamyl nitrite

4,6-difluoro-1,3-benzothiazol-2-amine

→

2-chloro-4,6-difluoro-1,3-benzothiazole

Выход 99.0%

Растворители

acetonitrile

—

tri(ethylene glycol) dimethyl ether

Условия реакции

Обработка

1. 1
   workup.STIRRINGThe reaction mixture was stirred at rt for 10 minutes
2. 2
   Температураheated at 50° C. for 2.5 h
3. 3
   ТемператураThe reaction mixture was cooled to rt
4. 4
   ЭкстракцияThe solution was extracted with EtOAc
5. 5
   ПромывкаThe organic layer was washed with HCl (1.0 M), water and brine
6. 6
   Фильтрацияfiltered
7. 7
   Концентрированиеconcentrated down

Методика

To a solution containing copper chloride (II) (0.87 g, 6.45 mmol) and tri(ethylene glycol) dimethyl ether (3 mL) in acetonitrile (50 mL) was added isoamyl nitrite (0.94 g, 8.06 mmol), and the reaction mixture was stirred at rt for 30 minutes. To this suspension was added dropwise a solution of 4,6-difluoro-1,3-benzothiazol-2-amine (1.0 g, 5.37 mmol) in tri(ethylene glycol) dimethyl ether (5 mL). The reaction mixture was stirred at rt for 10 minutes, and then heated at 50° C. for 2.5 h. The reaction mixture was cooled to rt, and then poured cautiously into cold aqueous 6 M HCl (200 mL). The solution was extracted with EtOAc. The organic layer was washed with HCl (1.0 M), water and brine, filtered and concentrated down to afford 2-chloro-4,6-difluoro-1,3-benzothiazole (1.1 g, 99%). 1H NMR (400 MHz, DMSO-d6) 7.05 (m, 1H), 7.36 (m, 1H).

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