Hydrochloric Acid → Methyl N-(3-chloro-4-hydroxyphenyl)carbamate

5 ml of water and 2.5 ml of 10% aqueous sodium hydroxide solution were carefully added to 1.70 g of 4-amino-2-chlorophenol cooled in an ice-water bath and 2 ml of methyl chloroformate were added dropwise to the resulting mixture. The reaction mixture was then stirred for 3 hours at room temperature, at the end of which it was acidified with 4 ml of 2N hydrochloric acid, and the resulting mixture was extracted with methylene; chloride. The resulting extract was washed with water and then dried over anhydrous sodium sulfate. The solvent was then removed by evaporation under reduced pressure to give a crude crystalline solid which was purified by column chromatography through silica gel using a 2:1 by volume mixture of hexane and ethyl acetate as the eluent to give 2.08 g (yield 87%) of the title compound as a pale brown crystalline solid.

1. temperaturecooled in an ice-water bath
2. extractionthe resulting mixture was extracted with methylene
3. extractionThe resulting extract
4. washwas washed with water
5. dry with materialdried over anhydrous sodium sulfate
6. customThe solvent was then removed by evaporation under reduced pressure
7. customto give a crude crystalline solid which
8. customwas purified by column chromatography through silica gel using a 2:1
9. additionby volume mixture of hexane and ethyl acetate as the eluent

ORD-Eintrag

ord-2368dd68468a480ea51565699944a8cf

Quelldatensatz

uspto-grants-1998_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05736487