HCID 18613617, compound → N-(4-chloro-3-methyl-5-isothiazolyl)-3-amino-4-hydroxyphenylacetamide

Temperature

35 °C

N-(4-Chloro-3-methyl-5-isothiazolyl)-4-hydroxy-3-nitrophenylacetamide (50 g, 0.15 mol), 1% w/w platinum on carbon (15 g) and N,N-dimethylformamide (400 ml) were charged to a 600 ml stainless steel hydrogenation vessel. Once purged the vessel was pressurised to 35 bar with hydrogen, stirring was started and the reaction was heated to 35° C. After 6 hours the uptake of hydrogen had stopped; the stirring and heating were turned off and the mixture was allowed to cool to ambient temperature. The vessel was vented, purged with nitrogen and was heated to 50° C. to ensure complete solution. The reaction mixture was filtered to remove the catalyst and the liquors concentrated under high vacuum to remove the N,N-dimethylformamide. The resultant residue was slurried in dichloromethane (300 ml), filtered, washed with dichlorometane (200 ml) and dried to give give N-(4-chloro-3-methyl-5-isothiazolyl)-3-amino-4-hydroxy-phenylacetamide (43.9 g) as a buff solid, m.p. 239-243° C.

1. customOnce purged the vessel
2. temperaturethe stirring and heating
3. temperatureto cool to ambient temperature
4. custompurged with nitrogen
5. temperaturewas heated to 50° C.
6. filtrationThe reaction mixture was filtered
7. customto remove the catalyst
8. concentrationthe liquors concentrated under high vacuum
9. customto remove the N,N-dimethylformamide
10. filtrationfiltered
11. washwashed with dichlorometane (200 ml)
12. customdried
13. customto give

ORD record

ord-c76dcb179279466d93adbfc90eed250c

Source dataset

uspto-grants-2003_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06544989B2