Reaktion #61854

Reaktionsgleichung

trifluoro-methanesulfonic acid 2-tert-butoxycarbonylamino-5-methyl-oxazol-4-yl ester

1-naphthaleneboronic acid

potassium acetate

→

5-methyl-4-naphthalen-1-yl-oxazol-2-ylamine

Ausbeute 14.0%

5-Methyl-4-naphthalen-1-yl-oxazol-2-ylamine

Ausbeute 14.0%

Lösungsmittel

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was removed under reduced pressure and to the resulting yellow oil
2. 2
   workup.ADDITIONwas added dichloromethane (18 mL) and trifluoroacetic acid (2 mL)
3. 3
   Sonstigethe solvent was removed under reduced pressure
4. 4
   workup.ADDITIONthe resulting oil was diluted with ethyl acetate
5. 5
   Waschenwashed with a saturated solution of sodium hydrogen carbonate, brine
6. 6
   Trocknendried over magnesium sulfate
7. 7
   Filtrationfiltered
8. 8
   Sonstigethe solvent removed under reduced pressure
9. 9
   Sonstigeto afford a brown oil
10. 10
    SonstigePurification by column chromatography

Vorschrift

A mixture of trifluoro-methanesulfonic acid 2-tert-butoxycarbonylamino-5-methyl-oxazol-4-yl ester (100 mg), 1-naphthaleneboronic acid (61 mg) palladium (0) tetrakis(triphenylphosphine) (17 mg), potassium acetate (85 mg) and 1,4-dioxane (5 mL) was heated at 180° C. for 24 hours. The solvent was removed under reduced pressure and to the resulting yellow oil was added dichloromethane (18 mL) and trifluoroacetic acid (2 mL). The mixture was stirred at room temperature for 1 hour and then the solvent was removed under reduced pressure, the resulting oil was diluted with ethyl acetate and washed with a saturated solution of sodium hydrogen carbonate, brine, dried over magnesium sulfate, filtered and the solvent removed under reduced pressure to afford a brown oil. Purification by column chromatography afforded 5-methyl-4-naphthalen-1-yl-oxazol-2-ylamine (30) (9 mg, 14%) as a white solid. 1H NMR (DMSO-D6): 2.15 (3H, s), 6.5 (2H, br s), 7.4-7.5 (4H, m), 7.85-7.90 (2H, m), 8.2 (1H, m). Mass Spectrum (m/z): 225 (M+H)+.

Quelle