Department of Chemical Technology, Poznan University of Technology, Poznan 60-965, Poland.
Institute of Plant Protection - National Research Institute, Poznan 60-318, Poland.
J Agric Food Chem. 2022 Mar 2;70(8):2545-2553. doi: 10.1021/acs.jafc.1c07750. Epub 2022 Feb 16.
In the framework of this study, dicationic herbicidal ionic liquids (HILs) containing tetramethylene-1,4-bis(decyldimethylammonium) and dodecylmethylene-1,12-bis(decyldimethylammonium), including two different herbicidal anions exhibiting different modes of action, were synthesized and characterized. One herbicide incorporated into the HILs was a tribenuron-methyl belonging to ALS inhibitors, while the second herbicidal anion was a synthetic auxin that acts as a growth regulator, namely 2,4-dichlorophenoxyacetate (2,4-D), 2-(2,4-dichlorophenoxy)propionate, (2,4-DP), 2,4,5-trichlorophenoxyacetate (2,4,5-T), 4-chloro-2-methylphenoxyacetiate (MCPA), 2-(4-chloro-2-methylphenoxy)propionate (MCPP), and 4-chlorophenoxyacetate (4-CPA). The obtained products were found to be unstable and decomposed, which can be attributed to the presence of an additional methyl group within the sulfonylurea bridge of the tribenuron-methyl. The synthesized HILs exhibited good affinity with polar and semipolar solvents, with ethyl acetate and hexane as the only solvents that did not dissolve the HILs. Greenhouse tests demonstrated that most of the obtained HILs were more effective than the reference herbicide containing tribenuron-methyl. The length of the alkyl chain in the cation also influenced the effectiveness of the HILs. Better effects were observed for dodecylmethylene-1,12-bis(decyldimethylammonium) cations compared to tetramethylene-1,4-bis(decyldimethylammonium). Therefore, the novel dicatonic HILs showed to integrate the advent of the combination of the different herbicides into a single molecule, enhance herbicidal efficacy, and reduce the risk of weed resistance due to the various modes of action of the applied treatment.
在这项研究中，合成并表征了含有四亚甲基-1,4-双（十二烷基二甲基铵）和十二亚甲基-1,12-双（十二烷基二甲基铵）的二价除草离子液体（HIL），其中包含两种不同的具有不同作用模式的除草阴离子。一种掺入 HIL 的除草剂是属于 ALS 抑制剂的三甲隆，而第二种除草阴离子是一种合成的生长素，用作生长调节剂，即 2,4-二氯苯氧基乙酸（2,4-D）、2-（2,4-二氯苯氧基）丙酸（2,4-DP）、2,4,5-三氯苯氧基乙酸（2,4,5-T）、4-氯-2-甲基苯氧基乙酸（MCPA）、2-（4-氯-2-甲基苯氧基）丙酸（MCPP）和 4-氯苯氧基乙酸（4-CPA）。发现所得产物不稳定并分解，这可归因于三甲隆的磺酰脲桥内存在额外的甲基。合成的 HIL 与极性和非极性溶剂具有良好的亲和力，乙酸乙酯和己烷是唯一不溶解 HIL 的溶剂。温室试验表明，大多数获得的 HIL 比含有三甲隆的参考除草剂更有效。阳离子中烷基链的长度也影响 HIL 的有效性。与四亚甲基-1,4-双（十二烷基二甲基铵）相比，十二亚甲基-1,12-双（十二烷基二甲基铵）的阳离子效果更好。因此，新型二价离子液体 HIL 显示出将不同除草剂的组合集成到单个分子中，提高除草效果，并降低由于应用处理的不同作用模式而导致杂草抗性的风险。
