Study On The Microwave Reaction Of Terpennoids And Ultrasound-assisted Extraction Of Flavonoids

The technology of synthesizing terpineyl acetate has been studied by using the method of microwave interval irradiation. The results showed that the optimized conditions were as the follows: the ratio of acetic anhydride to terpineol was 1.25:1,4% acetic anhydride were used as catalyst (based on rosin weight) under 100W microwave, and the irradiation time was 2h, respectively. The conversion of terpineol was at 96.92% and the yield of terpineyl acetate was 86.53% under optimum conditions. Compared with normal methods, it had higher efficiency, in which only one of eight reaction tine was needed.The synthesis of linalyl acetate was also investigated by using the same method. The optimum conditions were that the ratio of acetic anhydride to linalool was 2.5:1, 4% acetic anhydride was used as catalyst (based on rosin weight) under 100W microwave, and the irradiation time was 5h. The conversion of linalool was 76.71% and the yield of linalyl acetate was 61.48% under optimum conditions.The mechanism of synthesizing terpineyl and lynaly acetate under microwave interval irradiation has also been discussed preliminarily.Temperature rising, decarboxylation and isomerization of diterpenoid resin acids (rosin acids) under microwave irradiation were studied by using a N8C77 microwave oven, and the results showed that the temperature rising rate was greatly affected by the power of microwave irradiation, without decarboxylation but with some rosin isomerization. The results showed that the variations of rosin acid under microwave irradiation were mainly affected by heat effect of microwave.The technology of synthesizing rosin glycerin ester under microwave irradiation with microwave reactor at normal pressure was investigated, and the optimum conditions were that the ratio of rosin:glycerin:zinc oxide was 20:2.4:0.068, the power of microwave was 700W, reaction time was 1h, and the vacuum was no less than 0.095Mpa. Glycerin rosin ester, with acid value 9.65, softening point 80.7℃, Gardner color 7, and good solubility in benzene (1:1), has been prepared under optimum conditions, and its quality is according with the standard of 136~# glycerin rosin ester. Furthermore, the mechanism of synthesizing rosin glycerin ester under microwave irradiation was discussed preliminarily.On the other hand, the factors affecting ultrasound-assisted extraction of flavonoids from the leaves of Acer truncatum Bunge were studied with ultrasonic cleaner CX-250. The results showed that optimium conditions were that the power of ultrasonic was medium, volume ratio of material to solvent was 1:20, and extraction time was 30min for twice. The yield and purity of flavonoids were higher than those using normal methods, and the extraction time was only about one of ten in the normal methods. It shows remarkable potential for practical utilization.