反应详情

温度

80 °C

Zinc powder (65.37 g, 1 mol) and 3.27 g (50 mmol) of iodine are placed in 400 ml of toluene. This violet suspension is heated to 80° C. in an oil bath while stirring and treated within 80 minutes with a solution of 118.55 g (500 mmol) of ethyl 2-bromoheptanoate and 87.08 g (750 mmol) of acetoxyacetone in 100 ml of toluene. The exothermic reaction which sets in immediately can be held at 80°-90° C. by removing the oil bath. After a further 90 minutes at 80° C. the reaction mixture, cooled to room temperature, is treated with 400 ml of ice-water and then with 120 ml of 20% HCl and stirred for 30 minutes. Then, it is extracted three times with 500 ml of ether in a separating funnel. The ether phases are washed with 500 ml of sat. NaHCO3 solution and with 500 ml of sat. NaCl solution, dried over MgSO4 and concentrated on a rotary evaporator. The crude product distills at 110°-112° C./0.06 mbar and gives 49.64 g (43.5%) of 4-acetoxy-4-methyl-3-pentyl-tetrahydrofuran-2-one.

1. customThe exothermic reaction which
2. customcan be held at 80°-90° C.
3. customby removing the oil bath
4. temperaturecooled to room temperature
5. additionis treated with 400 ml of ice-water
6. stirringwith 120 ml of 20% HCl and stirred for 30 minutes
7. extractionThen, it is extracted three times with 500 ml of ether in a separating funnel
8. washThe ether phases are washed with 500 ml of sat. NaHCO3 solution and with 500 ml of sat. NaCl solution
9. dry with materialdried over MgSO4
10. concentrationconcentrated on a rotary evaporator
11. distillationThe crude product distills at 110°-112° C./0.06 mbar