新型2-烷氧基-5-苯基亚甲基-4H-咪唑啉-4-酮衍生物的合成与杀菌活性研究

Study on Synthesis and Fungicidal Activities of Novel 2-Alkoxy-5-phenylidene-4H-imidazolin-4-ones

应用烯基膦亚胺1与芳基异氰酸酯、醇的串联aza-Witting反应,合成了2-烷氧基-5-苯基亚甲基-4H-咪唑啉-4-酮衍生物3。对影响环化反应的温度和时间进行了优化,在优化条件20～70℃和1～4h下3a～3f的收率为35%～58%。提出了可能的环化反应机理。探讨了新型环化产物的波谱性质,其结构经元素分析、IR、1HNMR和MS确证。对所合成的新型杂环化合物的杀菌活性测试结果表明部分化合物表现出较好的抑菌活性,其中以3a活性最好,在50mg/L浓度时,对苹果轮纹菌的抑制率达到85%。

2-Alkoxy-5-phenylidene-4H-imidazolin-4-ones 3 were synthesized via tandem aza-Wittig reaction of vinyliminophosphorane 1, aromatic isocyanate and alcohols. The optimun conditions of the cyclization reaction were found. Under the optimun conditions (20～70 ℃ and 1～4 h), the yields of 3a～3f were 35%～58%. A possible mechanism for the cyclization reaction was suggested. The spectral properties of the new cyclized compounds were studied, and their structures were confirmed by elemental analysis, IR, ~1H NMR and MS. The fungicidal activities of the new heterocyclics compounds were tested, showing that some of the compounds exhibited good fungicidal activities. The best one was compound 3a which exhibited 85% inhibition of physalospora piricola when the concentration was 50 mg/L.