Hydrochloric Acid → 4-Chloro-2-[(3-chloropropyl)amino]-3-nitrobenzoic acid

A mixture of 6-chloro-7-nitro-1H-indole-2,3-dione (1.50 g, 6.80 mmol), 1-chloro-3-iodopropane (2.92 mL, 27.2 mmol) and cesium carbonate (8.86 g, 27.2 mmol) in N,N-dimethylacetamide (30 mL) was stirred at room temperature for 6 h. 1N Aqueous sodium hydroxide (30 mL) was added dropwise to the reaction mixture at 0° C., and the resultant mixture was stirred at room temperature for 15 min. 30% Aqueous hydrogen peroxide (1.16 mL) was added dropwise to the reaction mixture at 0° C., and the resultant mixture was stirred at room temperature for 15 min and acidified with 1N aqueous hydrochloric acid at 0° C. The resultant mixture was extracted with ethyl acetate. The extract was washed with water and brine, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by column chromatography on silica gel eluting with a 3% methanol/ethyl acetate mixture to give a crude solid, which was washed with diisopropyl ether/hexane to afford the title compound as an orange solid (1.39 g, 4.74 mmol, 70%).

1. extractionThe resultant mixture was extracted with ethyl acetate
2. washThe extract was washed with water and brine
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was purified by column chromatography on silica gel eluting with a 3% methanol/ethyl acetate mixture
7. customto give a crude solid, which
8. washwas washed with diisopropyl ether/hexane

ORD record

ord-a6d0d07608f24a089c3f6ac71a5b2064

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08901141B2