Trifluoroacetic acid → 2-(3-Cyclopropoxy-4-difluoromethoxyphenyl)-3-methyl-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one

To 1.10 g (2.30 mmol) of 2-(3-cyclopropoxy-4-difluoromethoxyphenyl)-3-methyl-5-(2-trimethylsilylethoxymethyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one obtained in Example 4-(b) were added 30 ml of dichloromethane and 6 ml of trifluoroacetic acid, and the mixture was stirred under room temperature for 2.5 hours. After completion of the reaction, the reaction mixture was concentrated under reduced pressure, 20 ml of methanol and 2 ml of 28% aqueous ammonia were added to the obtained solid, and the mixture was stirred under room temperature for 12 hours. Then, water was added to the solution, precipitated solid was collected by filtration, washed with water, and then, dried under reduced pressure. To the obtained dried material was added ethyl acetate to dissolve therein, diisopropyl ether was added to the solution and precipitated solid was collected by filtration. The obtained solid was dried under reduced pressure to obtain 0.54 g of the title compound as a white solid. (Yield: 67%)

1. customAfter completion of the reaction
2. concentrationthe reaction mixture was concentrated under reduced pressure, 20 ml of methanol and 2 ml of 28% aqueous ammonia
3. additionwere added to the obtained solid
4. stirringthe mixture was stirred under room temperature for 12 hours
5. additionThen, water was added to the solution
6. customprecipitated solid
7. filtrationwas collected by filtration
8. washwashed with water
9. customdried under reduced pressure
10. additionTo the obtained dried material was added ethyl acetate
11. dissolutionto dissolve
12. additiondiisopropyl ether was added to the solution
13. customprecipitated solid
14. filtrationwas collected by filtration
15. customThe obtained solid was dried under reduced pressure

ORD record

ord-5e4cbdd24a0a45bfb02460e22bed698c

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08450319B2