Crotyl chloride → 1-[1-(2-Butenyloxy)-2-methyl-2-propenyl]-4-methylbenzene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Solid potassium tert-butylate (47 g, 0.411 mol) was added portion-wise (ca 15 min) to a solution of 1-(4-methylphenyl)-2-methyl-2-propen-1-ol (96% pure, 46.27 g, 0.274 mol) in dry THF (500 ml) at room temperature under nitrogen (exothermic to 30° C.). After 1 more hour at room temperature, the reaction was cooled to 5° C. and tetra butyl ammonium iodide (5.2 g, 0.014 mol) was added followed by crotyl chloride (74.4 g, 0.822 mol) drop-wise. The reaction was warmed up to room temperature overnight and poured onto water (800 ml). The reaction was extracted twice with ethyl acetate. Each organic phase was washed with water and brine. Combined extracts were dried over solid anhydrous sodium sulfate. The solid was filtered off, rinsed with diethyl ether and the solvents were removed under vacuum. The product was purified by distillation under vacuum through a 20-cm Widmer column A 3:1 mixture of E/Z isomers was obtained (96% pure, 57.58 g, yield=93%). B.P.=74° C./0.005 mbar

Herkunft & Nachweise