Ammonium Chloride → 3-Aminobenzo[d]isoxazole-5-carbonitrile

To a stirring solution of potassium t-butoxide (8.4 g, 75 mmol) in THF (100 mL) was added acetone oxime (5.5 g, 75 mmol). After stirring for 30 min, a solution of 2-fluoroterephthalonitrile (10 g, 68 mmol) in THF (50 mL) was added; and stirring was continued for an additional 2 hr. Saturated aqueous ammonium chloride (100 mL) was added and the solvents were removed in vacuo. The residue was partitioned between EtOAc and brine. The layers were separated and the organic phase was washed once with brine, dried (MgSO4), filtered and concentrated. This crude solid was suspended in a solution of EtOH (150 mL), concentrated HCl (50 mL) and water (100 mL). This mixture was refluxed for 2 h. After cooling to room temperature, the solvents were removed in vacuo. The residue was treated with saturated aqueous sodium bicarbonate (200 mL), and the product was extracted by washing the aqueous layer three times with EtOAc. This organic solution was washed once with brine, dried (MgSO4), filtered and concentrated to give a pink colored solid (9.4 g, 86%).

1. stirringand stirring
2. waitwas continued for an additional 2 hr
3. customthe solvents were removed in vacuo
4. customThe residue was partitioned between EtOAc and brine
5. customThe layers were separated
6. washthe organic phase was washed once with brine
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. temperatureThis mixture was refluxed for 2 h
11. customthe solvents were removed in vacuo
12. additionThe residue was treated with saturated aqueous sodium bicarbonate (200 mL)
13. extractionthe product was extracted
14. washby washing the aqueous layer three times with EtOAc
15. washThis organic solution was washed once with brine
16. dry with materialdried (MgSO4)
17. filtrationfiltered
18. concentrationconcentrated

ORD-Eintrag

ord-2530e54034214faa8783aa4198465cdb

Quelldatensatz

uspto-grants-2003_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06534650B2