N-硝基-N-(2,6-二硝基-4-三氟甲基苯基)脲衍生物的合成及除草活性

Synthesis of N-Nitro-N-(2,6-dinitro-4-trifluoromethylphenyl)urea Derivatives and Their Herbicidal Activities

以2,6-二硝基-4-三氟甲基氯苯为起始原料,与氨水反应生成2,6-二硝基-4-三氟甲基苯胺;该苯胺与乙酰硝酸酯反应生成N-硝基-2,6-二硝基-4-三氟甲基苯胺;以三乙胺为缚酸剂,N-硝基-2,6-二硝基-4-三氟甲基苯胺与固体光气在二氯甲烷中反应,生成酰氯中间体;酰氯中间体再与取代苯胺反应得到了7种含N-硝基的不对称脲类化合物。产物经IR1、HNMR、质谱、元素分析表征。对目标化合物进行了除草生物活性测试,初步测试结果表明:当其水溶液质量浓度为500 mg/L时,脲基另一端的苯环为2-氯苯基、4-氯苯基、2-甲基苯基、4-甲基苯基时,这些化合物对稗草的校正根长抑制率和校正茎长抑制率都大于40%;但这些化合物对苋菜作用不明显,对苋菜的校正根长抑制率和校正茎长抑制率小于20%。

2, 6-Dinitro-4-trifluoromethylaniline （ Ⅰ ） was prepared from trifluoromethylchlorobenzene and ammonia water at first. And then Ⅰ reacted with 2, 6-dinitro-4- acetyl nitrate in conc. sulfuric acid to give N-nitro-2, 6-dinitro-4-trifluoromethylaniline （ Ⅱ ）. Ⅱ reacted with bis （trichloromethyl） carbonate in dichloromethane and produced the corresponding carbamoyl chloride （Ⅲ）. Treatment of Ⅲ with substituted anilines gave 7 novel N-nitro-N-（ 2, 6-dinitro-4- trifluoromethylphenyl） urea derivatives. Their structures were confirmed by ^1H NMR, IR, MS and elementary analysis. The herbicidal activities of these new compounds were screened. Preliminary biological tests show that, at the concentration of 500 mg/L, when the phenyl groups connected to another enol of the urea group are 2-chlorophenyl,4-chlorophenyl,2-methylphenyl and 4-methylphenyl, these compounds demonstrated more than 40% rectified inhibitory rate against Echinochloa crusgalli beauv L in both stem growth and root growth. All these target molecules have no obvious effects on Amaranthus retroflexus L, with inhibitory rate below 20%.