Jiang Kezhi, Zhang Ningwen, Zhang Hu, Wang Jianmei, Qian Mingrong
Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou, Zhejiang, China.
MOA Key Lab for Pesticide Residue Detection, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China.
PLoS One. 2015 Apr 9;10(4):e0121389. doi: 10.1371/journal.pone.0121389. eCollection 2015.
The gas phase pyrolysis of trichlorfon was investigated by the on-line gas chromatography - mass spectrometry (GC-MS) pyrolysis and theoretical calculations. Two reaction channels were proposed in the pyrolytic reaction, by analyzing the detected pyrolytic products in the total ion chromatography, including 2,2,2-trichloroacetaldehyde, dimethyl phosphite, and dichlorvos. Theoretical calculations showed that there is an intramolecular hydrogen bond between the hydroxyl group and the phosphate O atom in trichlorfon, through which the hydroxyl H atom can be easily transferred to phosphate O atom to trigger two pyrolytic channels. In path-a, migration of H atom results in direct decomposition of trichlorfon to give 2,2,2-trichloroacetaldehyde and dimethyl phosphite in one step. In path-b, migration of H atom in trichlorfon is combined with formation of the O-P bond to give an intermediate, followed by HCl elimination to afford dichlorvos. Path-a is kinetically more favorable than path-b, which is consistent with the GC-MS results.
通过在线气相色谱-质谱联用（GC-MS）热解和理论计算研究了敌百虫的气相热解。通过分析总离子色谱中检测到的热解产物，在热解反应中提出了两个反应通道，包括2,2,2-三氯乙醛、亚磷酸二甲酯和敌敌畏。理论计算表明，敌百虫中羟基与磷酸酯O原子之间存在分子内氢键，通过该氢键羟基H原子可容易地转移至磷酸酯O原子以引发两个热解通道。在路径a中，H原子的迁移导致敌百虫直接分解，一步生成2,2,2-三氯乙醛和亚磷酸二甲酯。在路径b中，敌百虫中H原子的迁移与O-P键的形成相结合生成中间体，随后消除HCl得到敌敌畏。路径a在动力学上比路径b更有利，这与GC-MS结果一致。
