Methyl iodide → 4-Methoxybenzo[d]oxazol-2-amine

Temperature

50 °C

To a stirred solution of 10 g (66 mmol) 2-amino-benzooxazol-4-ol in 100 ml tetrahydrofuran at room temperature was added portionwise 3.49 g (79.9 mmol) sodium hydride (55% dispersion in oil), and the mixture was then stirred for 1 h at 50° C. A solution of 14.5 ml (233 mmol) iodomethane in 500 ml tetrahydrofuran was then added dropwise over 3 h, while the reaction mixture was maintained at 50° C. The mixture was then poured onto water and extracted three times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over sodium sulfate, and concentrated in vacuo. Flash chromatography (dichloromethane then 2/98 methanol/dichloromethane) afforded 7.5 g (69%) 4-methoxy-benzooxazol-2-yl-amine as a brown crystalline solid. EI-MS m/e (%): 164 (M+, 100), 149 ([M−CH3]+, 23), 135 (46).

1. temperaturewas maintained at 50° C
2. additionThe mixture was then poured onto water
3. extractionextracted three times with ethyl acetate
4. washThe combined organic phases were washed with saturated brine
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated in vacuo

ORD record

ord-9cc819735c444ffc9635e18473b2f29b

Source dataset

uspto-grants-2006_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06992083B2