Southern rootworm (Diabrotica undecimpunctata howardi) affects several plants such as soybean, sorghum, wheat, cucumber, alfalfa, cucurbits and it is most damaging to corn and peanuts. The pheromone based “attract an...Southern rootworm (Diabrotica undecimpunctata howardi) affects several plants such as soybean, sorghum, wheat, cucumber, alfalfa, cucurbits and it is most damaging to corn and peanuts. The pheromone based “attract and kill” strategy is one of the powerful ways to control pest population. To address our key objective of the practical utility of the synthetic pheromone, we have developed a simple synthetic strategy to produce gram scale southern corn rootworm pheromone in nine simple steps starting from S-Citronellol. The present strategy takes advantage of the existing chiral center of commercially available S-Citronellol. To get the basic carbon skeleton of the pheromone, the main step in the synthetic strategy is coupling of aliphatic units through Wittig reaction. The phosphonium salt from a non-functionalized aliphatic bromide followed by Wittig reaction improved the overall yield in the multistep synthesis of this pheromone. The large-scale production of pheromone enabled us to test it in the field.展开更多
Some unsaturated compounds with the required （Z,Z）-double bonds configuration are synthesized through controlled ozonolysis process of 1,5,9-cyclododecatriene by determining the necessary amount of ozone passing thr...Some unsaturated compounds with the required （Z,Z）-double bonds configuration are synthesized through controlled ozonolysis process of 1,5,9-cyclododecatriene by determining the necessary amount of ozone passing through to selectively guarantee the breakage of a double bond while leaving other two bonds as （Z,Z）. The products were diagnosed by using NMR spectrum, infrared （IR） and mass spectrometer techniques. It is concluded that these products could widely be used in the synthesis of insect pheromones instead of insecticides and as useful intermediate compounds in many chemical reactions.展开更多
According to our retrosynthesis, the main chain of the target molecule could be constructed using a C5 ＋ C7 ＋ C5 strategy. The key induction reaction afforded chiral methyl group moieties using different Evans templ...According to our retrosynthesis, the main chain of the target molecule could be constructed using a C5 ＋ C7 ＋ C5 strategy. The key induction reaction afforded chiral methyl group moieties using different Evans templates with different configurations. Li_2 Cu Cl_4was effectively employed in the Csp^3 Csp^3 coupling protocol. The target molecular was obtained in a 12.6% overall yield with nine steps in the longest linear route.展开更多
文摘Southern rootworm (Diabrotica undecimpunctata howardi) affects several plants such as soybean, sorghum, wheat, cucumber, alfalfa, cucurbits and it is most damaging to corn and peanuts. The pheromone based “attract and kill” strategy is one of the powerful ways to control pest population. To address our key objective of the practical utility of the synthetic pheromone, we have developed a simple synthetic strategy to produce gram scale southern corn rootworm pheromone in nine simple steps starting from S-Citronellol. The present strategy takes advantage of the existing chiral center of commercially available S-Citronellol. To get the basic carbon skeleton of the pheromone, the main step in the synthetic strategy is coupling of aliphatic units through Wittig reaction. The phosphonium salt from a non-functionalized aliphatic bromide followed by Wittig reaction improved the overall yield in the multistep synthesis of this pheromone. The large-scale production of pheromone enabled us to test it in the field.
文摘Some unsaturated compounds with the required （Z,Z）-double bonds configuration are synthesized through controlled ozonolysis process of 1,5,9-cyclododecatriene by determining the necessary amount of ozone passing through to selectively guarantee the breakage of a double bond while leaving other two bonds as （Z,Z）. The products were diagnosed by using NMR spectrum, infrared （IR） and mass spectrometer techniques. It is concluded that these products could widely be used in the synthesis of insect pheromones instead of insecticides and as useful intermediate compounds in many chemical reactions.
基金Financial support from the National Natural Science Foundation of China(No.31301712)
文摘According to our retrosynthesis, the main chain of the target molecule could be constructed using a C5 ＋ C7 ＋ C5 strategy. The key induction reaction afforded chiral methyl group moieties using different Evans templates with different configurations. Li_2 Cu Cl_4was effectively employed in the Csp^3 Csp^3 coupling protocol. The target molecular was obtained in a 12.6% overall yield with nine steps in the longest linear route.
