Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 4-2-1 Takatsukasa, Takarazuka, Hyogo 665-8555, Japan.
J Agric Food Chem. 2021 Nov 10;69(44):12966-12973. doi: 10.1021/acs.jafc.1c03813. Epub 2021 Oct 26.
The photodegradation behavior of a new anilide fungicide, inpyrfluxam [3-difluoromethyl--[()-2,3-dihydro-1,1,3-trimethyl-1-inden-4-yl]-1-methylpyrazole-4-carboxamide] (), was investigated in aqueous buffer and nitrate solutions under irradiation with artificial sunlight (λ > 290 nm). In both media, mainly photodegraded via oxidation at the 3'-position of the Indane ring, cleavage of the C-N bond of the amide linkage and -phenyl ring bond, and finally mineralization to carbon dioxide. No isomerization of occurred at the 3'-position of the Indane ring. In the presence of nitrate ion, which originates from fertilizer in agricultural fields, the degradation of was significantly accelerated as compared with buffer solution, and the reaction rate was strongly correlated with the concentration of hydroxyl radicals derived from the photolysis of nitrate ions. The reaction rate constant of hydroxyl radicals with was determined to be 3.0 × 10 /M/s, which was higher than that of hydroxyl radicals with other pesticides possessing aromatic rings.
新型酰胺类杀菌剂茚虫威（[3-二氟甲基-[（-）-2,3-二氢-1,1,3-三甲基-1-茚满-4-基]-1-甲基吡唑-4-甲酰胺]）在人工阳光下（λ＞290nm）于水缓冲液和硝酸盐溶液中的光降解行为进行了研究。在这两种介质中，茚虫威主要通过茚满环 3'-位的氧化、酰胺键和 -苯基环键的断裂以及最终矿化为二氧化碳而降解。茚满环 3'-位没有发生异构化。在硝酸盐离子存在下，硝酸盐离子来源于农业领域的肥料，与缓冲溶液相比，茚虫威的降解明显加快，反应速率与光解生成的羟基自由基浓度强烈相关。羟基自由基与茚虫威的反应速率常数为 3.0×10^9/M/s，高于具有芳环的其他农药的羟基自由基。
