反应详情

To a suspension of 2-(4-fluoro-3-nitrophenyl)benzoxazole (see Working Example 15-2) (0.77 g, 3.0 mmol) in acetonitrile (10 mL) was added glycine tert-butyl ester hydrochloride (0.60 g, 3.6 mmol) and triethylamine (0.90 g, 9.0 mmol), and this was heated to reflux for 4 hours. After the reaction was complete, this was cooled to room temperature, water was added, and the precipitated crystals were filtered, washed with water and then dried. To a tetrahydrofuran solution (50 mL) of the residue obtained was added 10% palladium-carbon (50 mg). A hydrogen atmosphere was substituted in the flask, and this was stirred overnight at room temperature. 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 (0.40 g, 40% yield) as a light orange solid.

1. temperaturethis was heated
2. temperatureto reflux for 4 hours
3. filtrationthe precipitated crystals were filtered
4. washwashed with water
5. customdried
6. customTo a tetrahydrofuran solution (50 mL) of the residue obtained
7. filtrationthis was filtered through Celite
8. concentrationthe filtrate was concentrated
9. customThe residue obtained
10. customwas purified by silica gel column chromatography