Hydrochloric Acid → 6-Bromo-2-hydroxy-N-methyl-1-naphthamide

To a ice-cooled solution of 6-Bromo-2-hydroxy-1-naphthoic acid (10.0 g) and triethylamine (26.1 mL) in anhydrous THF (300 mL) was added dropwise methanesulfonyl chloride (7.0 mL), and the mixture was stirred for 90 min at room temperature. A solution of methylamine (2M in THF; 60 mL) was added, and the reaction mixture was further stirred for overnight at room temperature. The mixture was acidified with conc. HCl and extracted with ethyl acetate. The combined organic layer was washed with brine, dried over MgSO4 followed by concentrating in vacuo. The residue was washed hexane-ethyl acetate (1:1) to give a light brown powder. The powder was dissolved in THF-MeOH-4N-NaOH (6:1:1, 80 mL), and the mixture was heated at 70° C. for 30 min. After cooling to room temperature, the mixture was acidified with conc. HCl and concentrated in vacuo. The residue was washed with water and AcOEt to give the title compound (4.61 g) as light brown powder.

1. stirringthe reaction mixture was further stirred for overnight at room temperature
2. extractionextracted with ethyl acetate
3. washThe combined organic layer was washed with brine
4. dry with materialdried over MgSO4
5. concentrationby concentrating in vacuo
6. washThe residue was washed hexane-ethyl acetate (1:1)
7. customto give a light brown powder
8. temperaturethe mixture was heated at 70° C. for 30 min
9. temperatureAfter cooling to room temperature
10. concentrationconcentrated in vacuo
11. washThe residue was washed with water and AcOEt

ORD-Eintrag

ord-6864dfbe441749cb8056d3a80e426806

Quelldatensatz

uspto-grants-2003_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06649643B1