Reaction #69067

Reaction equation

4-Fluoro-3-hydroxybenzoic acid

DMF

(chloromethyl)cyclopropane

potassium carbonate

potassium iodide

→

title compound

1-(3-(cyclopropylmethoxy)-4-fluorophenyl)ethanamine

Solvents

water

Conditions

Workup

1. 1
   TemperatureThe reaction mixture was cooled to room temperature
2. 2
   Extractionthe resultant mixture was then extracted with toluene (10 mL)
3. 3
   WashThe organic layer was washed with brine (10 mL)
4. 4
   Dryingdried over anhydrous sodium sulfate
5. 5
   Concentrationconcentrated under reduced pressure
6. 6
   workup.DISSOLUTIONThe residue was dissolved in toluene (4.0 mL)
7. 7
   workup.ADDITIONTo the mixture, a solution of DIBAL in hexane (1.0 M, 7.6 mL) was then added dropwise at 0° C.
8. 8
   workup.STIRRINGthe reaction mixture was stirred at 0° C. for 2 hours
9. 9
   workup.ADDITIONTo the reaction mixture, water (1.0 mL) and an aqueous sodium hydroxide solution (1.0 M, 1.0 mL) were gradually added
10. 10
    OtherThe precipitate was removed by filtration
11. 11
    Washwashed with ethyl acetate (10 mL×5)
12. 12
    ConcentrationThen, the combined filtrate was concentrated under reduced pressure
13. 13
    workup.ADDITIONTo the residue, water (10 mL) was added
14. 14
    Extractionthe resultant mixture was then extracted with ethyl acetate (15 mL)
15. 15
    WashThe organic layer was washed with brine (10 mL)
16. 16
    Dryingdried over anhydrous sodium sulfate
17. 17
    Concentrationconcentrated under reduced pressure
18. 18
    OtherThe residue was purified by silica gel column chromatography (40% ethyl acetate/hexane)
19. 19
    workup.DISSOLUTIONThe residue was dissolved in dichloromethane (10 mL)
20. 20
    workup.ADDITIONTo the solution, manganese dioxide (5.0 g) was added at room temperature
21. 21
    Temperaturethe mixture was heated
22. 22
    Temperatureto reflux at 45° C. for 6 hours
23. 23
    TemperatureThe reaction mixture was cooled to room temperature
24. 24
    Otherthe precipitate was removed by filtration
25. 25
    Washwashed with chloroform (15 mL×4)
26. 26
    ConcentrationThen, the combined filtrate was concentrated under reduced pressure
27. 27
    workup.DISSOLUTIONThe residue was dissolved in THF (3.0 mL)
28. 28
    workup.ADDITIONTo the mixture, a solution of methylmagnesium bromide in THF (1.0 M, 1.4 mL) was added dropwise at 0° C.
29. 29
    workup.STIRRINGthe mixture was stirred at room temperature for 2 hours
30. 30
    workup.ADDITIONTo the reaction mixture, an aqueous saturated ammonium chloride solution (3.0 mL) was added at 0° C.
31. 31
    Extractionthe resultant mixture was then extracted with ethyl acetate (10 mL×2)
32. 32
    WashThe organic layer was washed with brine (10 mL)
33. 33
    Dryingdried over anhydrous sodium sulfate
34. 34
    Concentrationconcentrated under reduced pressure
35. 35
    workup.DISSOLUTIONThe obtained compound was dissolved in THF (5.0 mL)
36. 36
    workup.ADDITIONTo the mixture, diphenylphosphoryl azide (650 μL) and DBU (494 μL) were added dropwise at room temperature
37. 37
    workup.STIRRINGthe mixture was stirred for 1 hour
38. 38
    workup.ADDITIONTo the reaction mixture, brine (10 mL) was added
39. 39
    Extractionthe resultant mixture was then extracted with ethyl acetate (15 mL×2)
40. 40
    WashThe organic layer was washed with brine (10 mL)
41. 41
    Dryingdried over anhydrous sodium sulfate
42. 42
    Concentrationconcentrated under reduced pressure
43. 43
    OtherThe residue was purified by silica gel column chromatography (20% ethyl acetate/hexane)
44. 44
    workup.DISSOLUTIONThe obtained compound was dissolved in methanol (5.5 mL)
45. 45
    workup.ADDITIONTo the solution, 10% palladium-carbon (100 mg) was added
46. 46
    workup.STIRRINGthe reaction mixture was stirred at room temperature for 2 hours under a hydrogen atmosphere
47. 47
    OtherThe precipitate was removed by filtration through a pad of Celite
48. 48
    Washwashed with methanol (50 mL)
49. 49
    ConcentrationThen, the combined filtrate was concentrated under reduced pressure

Procedure

4-Fluoro-3-hydroxybenzoic acid (558 mg) was dissolved in DMF (5.0 mL). To the solution, (chloromethyl)cyclopropane (666 μL), potassium carbonate (990 mg), and potassium iodide (60 mg) were added, and the mixture was stirred at 90° C. for 6 hours. The reaction mixture was cooled to room temperature, water (10 mL) was then added thereto, and the resultant mixture was then extracted with toluene (10 mL). The organic layer was washed with brine (10 mL), dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was dissolved in toluene (4.0 mL). To the mixture, a solution of DIBAL in hexane (1.0 M, 7.6 mL) was then added dropwise at 0° C., and the reaction mixture was stirred at 0° C. for 2 hours. To the reaction mixture, water (1.0 mL) and an aqueous sodium hydroxide solution (1.0 M, 1.0 mL) were gradually added. The precipitate was removed by filtration and washed with ethyl acetate (10 mL×5). Then, the combined filtrate was concentrated under reduced pressure. To the residue, water (10 mL) was added, and the resultant mixture was then extracted with ethyl acetate (15 mL). The organic layer was washed with brine (10 mL), dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (40% ethyl acetate/hexane). The residue was dissolved in dichloromethane (10 mL). To the solution, manganese dioxide (5.0 g) was added at room temperature, and the mixture was heated to reflux at 45° C. for 6 hours. The reaction mixture was cooled to room temperature, and the precipitate was removed by filtration and washed with chloroform (15 mL×4). Then, the combined filtrate was concentrated under reduced pressure. The residue was dissolved in THF (3.0 mL). To the mixture, a solution of methylmagnesium bromide in THF (1.0 M, 1.4 mL) was added dropwise at 0° C., and the mixture was stirred at room temperature for 2 hours. To the reaction mixture, an aqueous saturated ammonium chloride solution (3.0 mL) was added at 0° C., and the resultant mixture was then extracted with ethyl acetate (10 mL×2). The organic layer was washed with brine (10 mL), dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The obtained compound was dissolved in THF (5.0 mL). To the mixture, diphenylphosphoryl azide (650 μL) and DBU (494 μL) were added dropwise at room temperature, and the mixture was stirred for 1 hour. To the reaction mixture, brine (10 mL) was added, and the resultant mixture was then extracted with ethyl acetate (15 mL×2). The organic layer was washed with brine (10 mL), dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (20% ethyl acetate/hexane). The obtained compound was dissolved in methanol (5.5 mL). To the solution, 10% palladium-carbon (100 mg) was added, and the reaction mixture was stirred at room temperature for 2 hours under a hydrogen atmosphere. The precipitate was removed by filtration through a pad of Celite and washed with methanol (50 mL). Then, the combined filtrate was concentrated under reduced pressure to obtain the title compound (412 mg) as a crude product.

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