Hydrogen Peroxide → 3-Ethyl-3-(3-nitrophenyl)-1,5-pentanediol

Temperatur

0 °C

To a solution of 3-ethyl-3-(3-nitrophenyl)-4-pentenoic acid (Preparation 60, assume 7.25 mmol) in tetrahydropyran (43 ml) at 0° C. was added sodium borohydride (0.55 g, 14.5 mmol) and the reaction mixture was stirred at 0° C. for 10 min. To the reaction mixture was added borontrifluoride tetrahydrofuran complex (2.72 g, 19.4 mmol) over 5 min. The reaction mixture was stirred under nitrogen at 0° C. for 30 min then it was allowed to warm to room temperature overnight. Ethanol (10 ml) was added cautiously, followed sequentially by water (10 ml), 2M aqueous sodium hydroxide solution (1.8 ml), water (10 ml) and finally 2M aqueous sodium hydroxide solution (1.8 ml). Solid sodium carbonate (1.8 g) was added followed by 30% w:w aqueous hydrogen peroxide solution (60 ml) and the reaction mixture was stirred at room temperature for 30 minutes. The mixture was filtered and the filtrate was partitioned between brine (100 ml) and ethyl acetate (100 ml). The phases were separated and the organic extract was dried (MgSO4), filtered and concentrated in vacuo to give the crude product. This was purified by silica (150 g) column chromatography eluting with a gradient of ethyl acetate:toluene: 0.880 ammonia (49:50:1 to 66:33:1) to give the title compound as a yellow oil (661 mg, 34% over 3 steps).

1. stirringThe reaction mixture was stirred under nitrogen at 0° C. for 30 min
2. temperatureto warm to room temperature overnight
3. filtrationThe mixture was filtered
4. customthe filtrate was partitioned between brine (100 ml) and ethyl acetate (100 ml)
5. customThe phases were separated
6. extractionthe organic extract
7. dry with materialwas dried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customto give the crude product
11. customThis was purified by silica (150 g) column chromatography
12. washeluting with a gradient of ethyl acetate

ORD-Eintrag

ord-9c5b3546b5ed4ef9b25c11d834957e46

Quelldatensatz

uspto-grants-2003_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06610711B2