Acetaldehyde → 3-(2-(N-tert-Butoxycarbonylamino)ethoxy)-4-(1-hydroxyethyl)-5-phenylisoxazole

Temperature

-70 °C

3-(2-(N-tert-Butoxycarbonylamino)ethoxy)-5-phenylisoxazole (0.8 g) was dissolved in tetrahydrofuran (16 ml), and butyllithium (1.6M hexane solution, 3.7 ml) was added dropwise thereto at -70° C. under a nitrogen atmosphere, and the mixture was stirred for 10 minutes. After acetaldehyde (0.22 ml) was added dropwise to the reaction mixture, the resulting mixture was stirred for 10 minutes and the temperature of the mixture was raised to 0° C. The mixture was then poured into ice-cold water and the pH of the mixture was adjusted to a value of 6 with an aqueous potassium dihydrogenphosphate solution. After the reaction mixture was extracted with ethyl acetate and the organic layer was washed with a saturated aqueous NaCl solution, the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=2/1) to obtain the title compound (0.90 g, 98%) as a colorless oil.

1. stirringthe resulting mixture was stirred for 10 minutes
2. temperaturethe temperature of the mixture was raised to 0° C
3. additionThe mixture was then poured into ice-cold water
4. extractionAfter the reaction mixture was extracted with ethyl acetate
5. washthe organic layer was washed with a saturated aqueous NaCl solution
6. customthe solvent was evaporated under reduced pressure
7. customThe residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=2/1)

ORD record

ord-1c4157d0ee1d49ba897d1c444f5ab932

Source dataset

uspto-grants-1999_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06005116