反应详情

温度

120 °C

78.0 g (about 0.71 mol) of 1,5-hexadien-3-ol, obtained by a Grignard reaction from allylmagnesium bromide and acrolein, were dissolved in 198.0 g (1.65 mol) of trimethyl orthoacetate and 3.0 g (0.04 mol) of propionic acid were then added. The reaction mixture was heated to 120° C. and the methanol formed during the reaction was distilled off over a 15 cm Widmer column. After 2 hours, the reaction mixture was held at 130° C. for a further 1 hour to complete the reaction and was then cooled to room temperature, diluted with 500 ml of tert-butyl methyl ether and the solution was washed twice with 100 ml of saturated sodium bicarbonate solution, dried with sodium sulphate and concentrated. Distillation of the resulting 128 g of crude product over a 20 cm Widmer column gave 51.6 g of olfactorily good methyl (E)-4,7-octadienoate of boiling point 76° C./17 mbar and with a purity of about 98%.

1. distillationwas distilled off over a 15 cm Widmer column
2. waitthe reaction mixture was held at 130° C. for a further 1 hour
3. customthe reaction
4. temperaturewas then cooled to room temperature
5. washthe solution was washed twice with 100 ml of saturated sodium bicarbonate solution
6. dry with materialdried with sodium sulphate
7. concentrationconcentrated
8. distillationDistillation of the resulting 128 g of crude product over a 20 cm Widmer column