Take 14.48g of acetic acid and 30.84g of geraniol, mix them uniformly and add them into a three-necked flask, add 5g of acidic functionalized ionic liquid catalyst, heat under reflux and stir, use a water separator to separate water, react at 110 °C for 2 hours, and extract with ether after cooling , the raffinate is the recovered catalyst, the ether is recovered under reduced pressure, and the geranyl acetate is obtained by distillation.
Catalyst preparation method: Weigh 4.0g of titanium sulfate and 2.0g of ethyl orthosilicate. Under the condition of ultrasonic assistance, the ultrasonic frequency is 40KHZ, and the co-co-polymer of Ti(OH)4 and Si(OH)4 is prepared by sol-gel method. Precipitation, then impregnated with 0.5mol/L sulfuric acid for 5 hours, dried at 120°C, and calcined at 550°C for 4 hours to obtain SO42-/TiO2-SiO2 solid super acid.
3.08g of natural geraniol (content 93.8%), 0.05g of SO42-/TiO2-SiO2 solid superacid and 4.04g of acetic anhydride were placed in a round-bottomed flask, heated in an oil bath under electromagnetic stirring and heated to 50°C to maintain this The temperature is 1 hour, connected to the vacuum distillation equipment of the water pump, the vacuum degree is 50mmHg, and the temperature is slowly raised to 90 ℃ to distill off the water, acetic acid and the remaining acetic anhydride generated by the reaction. Use a moist pH test paper to check whether the acetic acid is removed, and the distillation is completed. After cooling to room temperature, suction filtration, dry the solid, wash the solid with petroleum ether, distill the filtrate with a rotary evaporator to recover the petroleum ether, remove the petroleum ether by natural volatilization of the solid, put it in an oven, dry it, and use it for the next reaction. Under the condition of vacuum degree of 50mmHg and temperature of 90℃, 4.35g of geranyl acetate was obtained by distillation (the content of geranyl acetate was 94.5%, and the content of isomerized by-products was 0.2%).