Реакция #2286339

Уравнение реакции

hydrochloric acid

dimethyl-thiocarbamic acid S-(4-amino-2,6-dichloro-phenyl)ester

Dimethyl-thiocarbamic acid S-(4-amino-2,6-dichloro-phenyl)ester

potassium hydroxide

→

4-amino-2,6-dichloro-benzenethiol

Выход 69.0%

4-Amino-2,6-dichloro-benzenethiol

Выход 69.0%

Растворители

water

ethanol

Условия реакции

Обработка

1. 1
   ТемператураAt this time, the reaction was cooled to 25° C.
2. 2
   Экстракцияwas extracted with ethyl acetate (2×250 mL)
3. 3
   СушкаThe organics were dried with magnesium sulfate
4. 4
   Фильтрацияfiltered
5. 5
   Концентрированиеconcentrated under vacuum to an orange solid
6. 6
   Фильтрацияcollected by filtration
7. 7
   Промывкаwashed with chloroform
8. 8
   КонцентрированиеThe filtrate was concentrated under vacuum
9. 9
   Другоеpurified by flash chromatography (Merck Silica gel 60, 230-400 mesh, 85:15 petroleum ether/ethyl acetate)

Методика

A solution of dimethyl-thiocarbamic acid S-(4-amino-2,6-dichloro-phenyl)ester (81) (2.0 g, 7.5 mmol) in ethanol was treated with a 3N aqueous potassium hydroxide solution. The reaction was heated to 95° C. for 2 d. At this time, the reaction was cooled to 25° C. and was then acidified to pH=2 with a 3N aqueous hydrochloric acid solution. This solution was diluted with water (500 mL) and then was extracted with ethyl acetate (2×250 mL). The organics were dried with magnesium sulfate, filtered, and concentrated under vacuum to an orange solid. The solid was slurried in chloroform, collected by filtration and washed with chloroform. The filtrate was concentrated under vacuum and purified by flash chromatography (Merck Silica gel 60, 230-400 mesh, 85:15 petroleum ether/ethyl acetate) to afford 4-amino-2,6-dichloro-benzenethiol (82) (1.0 g, 69%) as a white solid; EI(+)-HRMS m/e calcd for C6H5Cl2NS (M+) 192.9520, found 192.9519. Exact Mass=192.9520; Molecular weight=194.08

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