反应 #2286339

反应方程式

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

收率 69.0%

4-Amino-2,6-dichloro-benzenethiol

收率 69.0%

溶剂

water

ethanol

反应条件

后处理

1. 1
   温度At this time, the reaction was cooled to 25° C.
2. 2
   萃取was extracted with ethyl acetate (2×250 mL)
3. 3
   干燥The organics were dried with magnesium sulfate
4. 4
   过滤filtered
5. 5
   浓缩concentrated under vacuum to an orange solid
6. 6
   过滤collected by filtration
7. 7
   洗涤washed with chloroform
8. 8
   浓缩The filtrate was concentrated under vacuum
9. 9
   其他purified by flash chromatography (Merck Silica gel 60, 230-400 mesh, 85:15 petroleum ether/ethyl acetate)

实验过程

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

来源