5种甲氧基多溴联苯醚的羟基化产物测定及反应机理分析

Detection of hydroxylated products of five MeO–PBDEs with hydroxyl radical and analysis of the reaction mechanism

测定天然水环境中检出的4’-MeO-BDE-17,5-MeO-BDE-47,5’-MeO-BDE-99,6-MeO-BDE-47和6-MeOBDE-855种甲氧基多溴联苯醚(MeO-PBDEs)与羟基自由基(·OH)反应的羟基化产物(HO-MeO-PBDEs)。采用实验检测与量子化学计算相结合的方法推测出可能生成的HO-MeO-PBDEs产物。5种MeO-PBDEs与·OH反应的产物中,只在5-MeO-BDE-47溶液中检出一种HO-MeO-PBDEs产物,来源于5-MeO-BDE-47的·OH加成反应,量子化学计算预测该产物可能为5-MeO-5’-HO-BDE-47,其余4种MeO-PBDEs溶液中均未检出HO-MeO-PBDEs产物。甲氧基和溴取代模式可以显著影响MeO-PBDEs生成HO-MeO-PBDEs产物。

Five MeO-PBDEs including 4’-MeO-BDE-17,5-MeO-BDE-47,5’-MeO-BDE-99,6-MeO-BDE-47 and 6-MeO-BDE-85 were selected to detect their hydroxylated products (HO-MeO-PBDEs) in the reaction with hydroxyl radical (· OH). HO-MeO-PBDEs were deduced by experimental detection combined with quantum chemical computation methods. Among five MeO-PBDEs, only one HO-MeO-PBDEs product was detected for 5-MeO-BDE-47 arising from · OH addition, which was hypothesized to be 5-MeO-5’-HO-BDE-47 by quantum chemical computation. No HO-MeO-PBDEs products can be detected for other four MeO-PBDEs. The generation of HO-MeO-PBDEs products between MeO-PBDEs and · OH is susceptible to substitution patterns of bromine andmethoxyl substituent of MeO-PBDEs.