反应详情

温度

75 °C

To a solution of 2-oxo-2,3-dihydro-1,3-benzoxazole-6-carbaldehyde (Intermediate 7, 300 mg, 1.84 mmol) in DMF (10 mL) were added potassium carbonate (633 mg, 4.58 mmol) and (3-bromopropoxy)(tert-butyl)dimethylsilane (0.47 mL, 2.03 mmol), and the resulting mixture was heated to 75° C. Upon complete disappearance of starting material (ca 16 hours), the solvent was removed under reduced pressure and the solid residue was treated with CH2Cl2 and stirred for 5 min. The suspension was filtered through Celite® and the solid residue washed with additional CH2Cl2. The filtrate was concentrated to dryness and the crude was purified by column chromatography over silica gel, eluting with Hexane:Et2O (from 0 to 32% of Et2O) to give the title compound as a white solid (550 mg, 89% yield).

1. customUpon complete disappearance of starting material (ca 16 hours), the solvent was removed under reduced pressure
2. additionthe solid residue was treated with CH2Cl2
3. filtrationThe suspension was filtered through Celite®
4. washthe solid residue washed with additional CH2Cl2
5. concentrationThe filtrate was concentrated to dryness
6. customthe crude was purified by column chromatography over silica gel
7. washeluting with Hexane