Reaktion #162038

Reaktionsgleichung

Cholestanol

Potassium tert-butoxide

tert-Butyl bromoacetate

→

product

Ausbeute 76.0%

tert-Butyl 2-(cholestan-3-yloxy)acetate

Ausbeute 76.0%

Lösungsmittel

toluene

Toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture was stirred overnight at room temperature
2. 2
   Waschenthe solution was washed with brine (50 mL)
3. 3
   ExtraktionThe aqueous phase was extracted with toluene (30 mL) before all organic phases
4. 4
   Trocknendried (Na2SO4)
5. 5
   Sonstigethe solvent evaporated
6. 6
   SonstigeThe crude product was purified

Vorschrift

Cholestanol (0.662 g, 1.703 mmol) was dissolved in toluene (13 mL). Potassium tert-butoxide (573 mg, 5.11 mmol) was added in one portion. The mixture was stirred at room temperature for 3 hours. tert-Butyl bromoacetate (503 μL, 3.406 mmol) was added drop-wise and the mixture was stirred overnight at room temperature. Toluene (20 mL) was added and the solution was washed with brine (50 mL). The aqueous phase was extracted with toluene (30 mL) before all organic phases were combined, dried (Na2SO4) and the solvent evaporated. The crude product was purified using column chromatography (SiO2; Hexane:EtOAc, 200:1 to 200:20) to yield the white solid product (0.65 g, 76% yield). 1H NMR (400 MHz, CDCl3) δ: 3.98 (s, 2H, CH2O), 3.30 (m, 1H, CHO), 1.97-0.56 (m, 31H), 1.46 (s, 9H, CH3), 0.89 (d, 3H, J=6.1, CH3), 0.85 (d, 3H, J=2.0, CH3), 0.84 (d, 3H, J=1.4, CH3), 0.79 (s, 3H, CH3), 0.64 (s, 3H, CH3).

Quelle