Pyridine → 4-Methyl-7-nitro-1H-indole-3-carbonitrile

Temperature

60 °C

Into 100 ml of dimethylformamide was dissolved 2.21 g (10.8 mmol) of the compound of Production Example 5 followed by adding 900 mg (13.0 mmol) of hydroxylamine hydrochloride and 1.05 ml (13.0 mmol) of pyridine thereto. After heating at 60° C. under stirring for 40 minutes, 53.9 mmol of 1,1′-carbonyldiimidazole (53.9 mmol) were added to the reaction solution under ice-cooling. After heating at 60° C. for further 30 minutes under stirring, 3.0 ml (21.5 mmol) of triethylamine was added to the reaction solution followed by heating at the same temperature for further 1 hour under stirring. To the reaction mixture was added 50 ml of ice water under ice-cooling followed by extracting with ethyl acetate. The organic layer was washed with water and brine successively, dried over magnesium sulfate and concentrated to dryness. To the resulting residue was added a mixed solution of tert-butyl methyl ether and hexane, and the resulting crystals were collected by filtration to give 1.95 g of the title compound.

1. temperaturecooling
2. temperatureAfter heating at 60° C. for further 30 minutes
3. stirringunder stirring
4. temperatureby heating at the same temperature for further 1 hour
5. stirringunder stirring
6. temperaturecooling
7. extractionby extracting with ethyl acetate
8. washThe organic layer was washed with water and brine successively
9. dry with materialdried over magnesium sulfate
10. concentrationconcentrated to dryness
11. additionTo the resulting residue was added a mixed solution of tert-butyl methyl ether and hexane
12. filtrationthe resulting crystals were collected by filtration

ORD record

ord-ca62b03bef614c458271959dd89358e4

Source dataset

uspto-grants-2004_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06673787B2