2种二芳醚农药中间体的合成

目的]二芳醚是重要的农药中间体,用于合成多种重要的杀虫剂,如一些拟除虫菊酯、杀菌剂如醚唑等农药。3,4’-二氯二苯醚和3-甲基二苯醚分别是醚唑和戊菊酯的关键中间体,传统上采用铜粉为催化剂合成效率和选择性欠佳,为此,对2种二芳醚中间体合成进行优化和改进。方法]采用商用铜粉和自制高分散铜为催化剂,分别对溶剂、反应摩尔比、反应温度、反应时间进行优化合成2种二芳醚中间体。结果]3,4’-二氯二苯醚的选择性达86.7%,收率为82.2%;3-甲基二苯醚的收率为96.8%。结论]实验结果显示高分散铜的催化活性和选择性都好于传统Ullmann反应催化剂。

Syntheses of Two Diaryl Ethers for Pesticide Intermediates

Diaryl ether are an important intermediate of the pesticide,which are widely used in synthesis of insecticides such as pyrethroids,and fungicides such as dienoconazole.3,4’-Dichlorodiphenyl ether and 3-methyl diphenyl ether are key intermediates of dienoconazole and fenvalerate,respectively.Traditionally,synthetic effeciency and selectivity are poorer when powder Cu was used as catalyst,so in this paper,the syntheses of the two diaryl ethers were optimized and improved.Methods] Commercial available powder Cu and high-dispersed Cu made by ourself are used as catalysts,a series of synthetic conditions such as solvents,various molar ratio of substrates,reaction temperature,reaction time,etc.are observed and optimized to synthesize these two diaryl ether intermediates.Results] the selectivity of 3,4’-dichlorodiphenyl ether was up to 86.7% with yield of 82.2%,while the yield(96.8%) of 3-methyl diphenyl ether was obtained.Conclusions] the experiment results showed that the catalytic activity and selectivity of high-dispersed copper are both better than that of traditional Ullmann reaction catalyst.