A convenient, green method to synthesize 4′-(bromomethyl)-2-cyanobiphenyl was developed, where visible light is used to initiate the radical chain reaction and the H₂O₂/HBr system as the bromine source. A range of solvents was tested, and a final multigram protocol was developed to give a good yield of 71% of product with 97% purity and no other purification than simple filtration and wash. Diethyl carbonate was found to be an efficient greener solvent alternative to classical solvents such as carbon tetrachloride and chlorobenzene, and 2-propanol, also considered a green solvent, was suitable for precipitation and washing in the purification step.

中文翻译：

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一种简便的多克级光诱导合成 4'-(溴甲基)-2-氰基联苯的方法

开发了一种方便、绿色的4'-(溴甲基)-2-氰基联苯合成方法，该方法利用可见光引发自由基链式反应，以H ₂ O ₂ /HBr体系作为溴源。测试了一系列溶剂，并开发了最终的多克方案，产物收率高达 71%，纯度为 97%，除了简单的过滤和洗涤之外没有其他纯化。人们发现碳酸二乙酯是一种有效的绿色溶剂，可以替代四氯化碳和氯苯等经典溶剂，而 2-丙醇也被认为是绿色溶剂，适合在纯化步骤中进行沉淀和洗涤。