Ethyl Bromide → 8-Ethoxy-2,6-dimethyl-nona-2,6-dien

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

THF (500 mL) and sodium hydride (60%, 52 g, 1.3 mol) were charged to a flame dried 2 L reaction flask equipped with a thermometer, a mechanical stirrer, a condenser, and an addition funnel. 8-Hydroxy-2,6-dimethyl-nona-2,6-diene (obtained as detailed above) was added dropwise while allowing the temperature to rise no higher than 50° C. After the addition was completed, the reaction mixture was aged for 1 hour. Ethyl bromide (142 g, 1.3 mol.) was added dropwise for over 2 hours. The reaction mixture was then heated to 60° C. and aged until the conversion rate was shown to be over 90%. The reaction mixture was cooled to lower than 30° C. and quenched by the slow addition of HCl (pH<5, 10%). The layers were split. The aqueous phase was extracted three times with toluene (100 mL). The extracts were added to the crude reaction mixture, which was then washed with saturated sodium bicarbonate followed by saturated salt solution and dried over anhydrous sodium sulphate. The crude reaction mixture was concentrated. The solvents were recovered via a rotary evaporator. Fractional distillation provided the compound 8-ethoxy-2,6-dimethyl-nona-2,6-dien with a boiling point of 125° C. at a pressure of 4.5 mmHg.

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