Reaktion #161401

Reaktionsgleichung

hydrogen

triethylamine

4-aminocyclohexanol hydrochloride

2-(4-Fluoro-3-nitrophenyl)benzoxazole

2-(4-fluoro-3-nitrophenyl)benzoxazole

→

title compound

Ausbeute 67.2%

2-(2-(4-hydroxycyclohexyl)aminoanilin-5-yl)benzoxazole

Ausbeute 67.2%

Lösungsmittel

methanol tetrahydrofuran

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthis was heated
2. 2
   Temperaturto reflux for 2 hours
3. 3
   Sonstigethe crystals precipitated by the addition of water
4. 4
   Filtrationwere filtered
5. 5
   WaschenAfter the crystals were washed with water, they
6. 6
   Sonstigewere dried under reduced pressure
7. 7
   Temperaturwith heating
8. 8
   Sonstigeto give crystals that
9. 9
   workup.STIRRINGthis was stirred at room temperature for 8 hours
10. 10
    Filtrationthis was filtered through Celite
11. 11
    Einengenthe filtrate was concentrated
12. 12
    SonstigeThe residue obtained
13. 13
    Sonstigewas purified by silica gel column chromatography

Vorschrift

2-(4-Fluoro-3-nitrophenyl)benzoxazole (see Working Example 15-2) (0.60 g, 2.3 mmol) was added to an acetonitrile (20 mL) solution containing triethylamine (0.70 g, 7.0 mmol) and 4-aminocyclohexanol hydrochloride (0.53 g, 2.5 mmol), and this was heated to reflux for 2 hours with stirring. After the reaction was complete, this was cooled to room temperature, and the crystals precipitated by the addition of water were filtered. After the crystals were washed with water, they were dried under reduced pressure with heating to give crystals that were added to a solution of a solvent mixture of methanol/tetrahydrofuran (1:1, 20 mL) including 10% palladium-carbon (50 mg). A hydrogen atmosphere was substituted in the flask, and this was stirred at room temperature for 8 hours. After the reaction was complete, this was filtered through Celite and the filtrate was concentrated. The residue obtained was purified by silica gel column chromatography to yield the title compound (0.50 g, 67% yield) as pale red crystals.

Quelle