1-芳基-2-苯基-3-甲基-3-异丙基-2-氧代-1,4,2-二氮磷杂环戊-5-酮的合成及除草活性

Synthesis and Herbicidal Activity of 1 Aryl 2 phenyl 3 methyl 3 isopropyl 1,4,2 diazaphospholidin 5 one 2 oxides

利用取代苯基脲与苯基二氯化膦和３－甲基－２－丁酮进行的类Ｍａｎｎｉｃｈ反应合成了１５种新的１，４，２－二氮磷杂环戊－５－酮类化合物（２ａ＿２ｏ），其结构经１ＨＮＭＲ，ＩＲ，ＭＳ和元素分析证实．根据ＮＭＲ谱分析，反应主要生成顺式几何异构体．除草活性测试表明，目标化合物对阔叶杂草具有很好的选择性除草活性。

A series of 1 aryl 2 phenyl 3 methyl 3 isopropyl 1,4,2 diazaphospholidin 5 one 2 oxides(2a_2o)have been synthesized by the Mannich type reaction of substituted phenyl ureas, phenyldichlorophosphine and 3 methyl 2 butanone, and their structures were confirmed by elemental analysis, NMR, IR and MS. On the basis of NMR analyses, we found that the cis isomers, in which the bigger group isopropyl and the phenyl group linked with the phosphorus atom are at the opposite side, are generated preferably in the reaction. The results of preliminary bioassay show that compounds 2 possess an excellent herbicidal activity selectively against rape. The structure herbicidal activity relationship(SAR) has also been discussed. Their herbicidal activities for the same substituent at different positions and those for different substituents at the same position are compared.