HCID 55297457, compound → 5-Fluoro-1,2,3,4-tetrahydroquinoline

To a solution of 5-fluoro-2,3-dihydro-1H-quinolin-4-one obtained in Reference Example 3 (64 mg) in trifluoroacetic acid (5 ml), triethylsilane (0.37 ml) was added and stirred at room temperature for 16 hours. After distilling off the solvent under reduced pressure, the residue was diluted with water, adjusted to pH 11 by addition of 1M aqueous sodium hydroxide, and extracted with diethyl ether. The organic layer was washed with brine, dried over anhydrous magnesium sulfate and then filtered to remove the desiccant, followed by distilling off the solvent under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluting solvent: n-hexane:ethyl acetate=3:1). The resulting residue was diluted with chloroform, added to 1M aqueous hydrochloric acid (15 ml) and partitioned. The aqueous layer was adjusted to pH 11 by addition of 2.5M aqueous sodium hydroxide, and extracted with ethyl acetate. The organic layer was washed with brine, dried over anhydrous magnesium sulfate and then filtered to remove the desiccant, followed by distilling off the solvent under reduced pressure to give the titled compound, i.e., 5-fluoro-1,2,3,4-tetrahydroquinoline (39 mg) as a light-yellow oil.

1. additionwas added
2. distillationAfter distilling off the solvent under reduced pressure
3. additionthe residue was diluted with water
4. additionadjusted to pH 11 by addition of 1M aqueous sodium hydroxide
5. extractionextracted with diethyl ether
6. washThe organic layer was washed with brine
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationfiltered
9. customto remove the desiccant
10. distillationby distilling off the solvent under reduced pressure
11. customThe resulting residue was purified by silica gel column chromatography (eluting solvent: n-hexane:ethyl acetate=3:1)
12. additionThe resulting residue was diluted with chloroform
13. additionadded to 1M aqueous hydrochloric acid (15 ml)
14. custompartitioned
15. additionThe aqueous layer was adjusted to pH 11 by addition of 2.5M aqueous sodium hydroxide
16. extractionextracted with ethyl acetate
17. washThe organic layer was washed with brine
18. dry with materialdried over anhydrous magnesium sulfate
19. filtrationfiltered
20. customto remove the desiccant
21. distillationby distilling off the solvent under reduced pressure

ORD record

ord-a1f89558b18744ea95eef69a0d1cd6d2

Source dataset

uspto-grants-2012_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08222417B2