Study On The Synthesis Of The Sex Pheromone Of The Madeira Mealybug

In recent years, a new cross-disciplinary–the chemical ecology has attracted wide att-ention. Biologically active substances involved in the chemical ecology are a source of dev-elopment of biological pesticides. Security conditions of ecological agriculture, it uses natu-ral bio-chemical interaction between the law to increase agricultural production and controlpests. Chemical pheromone is the most important contact information in the inside of insect.Pheromone signals are like radio waves password. Only the same individual can be identifid-d. Insect sex pheromones can be used to control pests. The insect pheromone was used to c-ontrol pests, because it has excellent property of high specificity. Thus, it does not hurt its e-nemies. It will not cause environmental pollution and resistance, so it is what we call the"third generation pesticides." The application of insect sex pheromones to pest control has o-pened up a new field. Its research and use are rapidly moving forward.Insect sex pheromone plays an important role in biological control against insect, beca-use of its high activity and strong specificity. The mealybug female sex pheromone obtainsmore and more attentions. As a big agricultural country, it is necessary for our country to re-search and develop mealybug sex pheromone which is a new type of pesticides. The paperuses natural chiral3-carene as the original raw material, by continuous three-step reaction,synthtize the key intermediate of dimethyl3,3-dimethyl-cyclopropane-1,2-dicarboxylate.The compound is the key intermediate for the preparation of two kinds of mealybug femalesex pheromone and has an important significance in synthesis research of insect sex phero-mone. Moreover, synthetic route has the advatages of broad source of raw materials, mildreaction conditions and so on.Firstly, the paper introduce the allylic oxidation of3-carene. The result shows that3-ca-rene-2,5-dione could be synthesized by allylic oxidation of3-carene with CuCl2/AC, TBH-P and O2in a solution of MeCN. Single factor design experiments were designed to optim-ize the synthesis conditions for obtaining desired yield. The optimal conditions are reactiontemperature as45℃, the molar ratio of CuCl2to3-carene as1%, the volume ratio of3-care-ne to TBHP as1:3, reaction time as12h.The supported CuCl2/AC can be reused three tim-es.Under optimal conditions, the conversion of3-carene was up to100%and the selectivityof3-carene-2,5-dione could reach78%.Secondly, the paper introduce the ring-opening reaction of3-carene-2,5-dione. Firstly, we used supported potassium permanganate as oxidant and various factors that effect thereaction had been discussed. We prepare supported potassium permanganates which weresupported on SiO2and its structures were characterized by XRD. However, we found thatthe yield of3,3-dimethyl-cyclopropane-1,2–dicarboxylic acid isn’t very high. Thus, wechoose no supported potassium permanganate as oxidant. We examined the impact of vari-ous factors on the reaction. We got the optimal condations, which is reaction temperature as50℃, the molar ratio of KMnO4to3,3-dimethyl-cyclopropane-1,2-dicarboxylic acid as5,the volume ratio of acetic acid to water as20:1, reaction time as4h.Under the optimal con-dations,the conversion of verbenone could reach100%and the yield of3,3-dimethyl-cyclo-propane-1,2-dicarboxylic acid could reach75%. By comparison, the results showed thatusing potassium permanganate as oxidant would get high yield by severe reaction.Thirdly, the paper introduce the esterification reaction of3,3-dimethyl-cyclopropane-1,2-dicarboxylic acid to synthesis dimethyl3,3-dimethyl-cyclopropane-1,2-dicarboxylateby Fischer esterification. Thepaper also investigate the effects of different water-carryingagent, PH, reaction time and temperature on esterification of3,3-dimethyl-cyclopropane-1,2-dicarboxylic acid.The results showed that cyclohexane was the best water entrainer, themole ratiomethanol of dimethyl3,3-dimethyl-cyclopropane-1,2-dicarboxylate as1:4, reac-tion temperatureas60℃，reaction time2h.Under the optimal, the conversion is98%and theyield is75%.Fourthly, the paper introduce SN2reaction of3,3-dimethyl-cyclopropane-1,2-dicerbo-xylic acid to synthesis dimethy3,3-dimethyl-cyclopropane-1,2-dicarboxylate. Na2CO3，Hexadecyl trimethyl ammonium Bromide（CTAB）, CH3I were added oderly. Under thesame conditions, the yield of dimethyl3,3-dimethyl-cyclopropane-1,2-dicarboxy-late is68.44%.Fifthly, the target products were analyzed and identified by IR,1HNMR, MS and opti-cal rotation.Sixthly, the paper got dimethyl3,3-dimethyl-cyclopropane-1,2-dicarboxylate，which isthe synthesis of key intermediate of the Sex Pheromone of the Madeira mealybug.