Hydroquinone → 4-Isopropoxyphenol

Beteiligte Stoffe

Reaktionsschritte

To a solution of hydroquinone (55.7 g, 0.5 mol) and 2-iodopropane (57.5 g, 0.33 mol) in ethanol was added a solution of potassium hydroxide (78.5 g, 0.5 mol) in water (100 mL). The dark brown solution was then refluxed for 16 hours. Ethanol was removed and the aqueous phase was acidified with 2N HCl and extracted with ethyl acetate (3×200 mL). The combined organic layers were washed with brine, dried (MgSO4) and filtered. The filtrate was concentrated in vacuo to give over 70 g of crude material, which was triturated with dichloromethane and filtered. The filtrate was concentrated and purified on silica gel (5˜35% ethyl acetate/hexane) to give 23.0 g of product as a brown oil (46% yield). 1H NMR (300 MHz, CDCl3) δ ppm 1.30 (d, J=5.88 Hz, 6H) 4.30-4.50 (m, 1H) 4.78 (s, 1H) 6.66-6.86 (m, 4H). MS (ESI): m/z 151 (M−H). 1H NMR (300 MHz, CDCl3) δ ppm 8.31 (d, J=1.84 Hz, 1H) 7.99 (dd, J=8.46, 1.84 Hz, 1H) 7.77 (d, J=9.19 Hz, 1H) 7.20-7.34 (m, 2H) 6.89-7.01 (m, 2H) 4.48-4.62 (m, 1H) 2.65 (s, 3H) 1.37 (d, J=5.88 Hz, 6H). MS m/z (DCI) 405.1 (M+H)+.

Herkunft & Nachweise