A cost-effective and expeditious one-pot synthesis of 1-(2-bromo-1-arylethyl)-1H-benzotriazoles has been devised by reacting styrene and their derivatives with 1H-benzotriazole in presence of N-bromosuccinimide in anhydrous CH₂Cl₂ at room temperature. Further, the resulted compounds undergo E₂-ellimination to afford the respective 1-(1-aryl-vinyl)-1H-benzotriazoles. At the end, 1-(1-phenylvinyl)-1H-benzotriazoles underwent benzotriazole ring cleavage (BtRC) under free radical condition to produce phenanthridine as the final product.

中文翻译：

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通过NBS合成1-（2-溴-1-芳基乙基）-1 H-苯并三唑促进了1 H-苯并三唑向烯烃的加成：苯并三唑环裂解的相关性

通过使苯乙烯及其衍生物与1 H-苯并三唑在N-溴代琥珀酰亚胺存在下于无水CH中反应，已设计出一种经济高效的一锅法合成1-（2-溴-1-芳基乙基）-1 H-苯并三唑₂ Cl ₂在室温下。此外，将所得的化合物进行E _2-消除，以提供相应的1-（1-芳基-乙烯基）-1 H-苯并三唑。最后，在自由基条件下对1-（1-苯基乙烯基）-1 H-苯并三唑进行苯并三唑环裂解（BtRC），以产生菲啶作为最终产物。