An improved and efficient bromination of 3,5-bis(trifluoromethyl)benzene was developed. A safe and reliable preparation of the potentially explosive 3,5-bis(trifluoromethyl)phenyl Grignard and 3-trifluoromethylphenyl Grignard reagents, from the precursor bromides, is described. Reaction System Screening Tool (RSST) and Differential Thermal Analysis (DTA) studies suggest these trifluoromethylphenyl Grignard reagents can detonate on loss of solvent contact or upon moderate heating. When prepared and handled according to the methods described herein, these Grignard reagents can be safely prepared and carried on to advanced intermediates.

中文翻译：

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3,5-双（三氟甲基）苯乙酮的改进制备方法和3,5-双（三氟甲基）苯基格氏试剂制备中的安全性考虑。

开发了一种改进的高效溴化3,5-双（三氟甲基）苯。描述了从前体溴化物安全可靠地制备潜在爆炸性的3,5-双（三氟甲基）苯基格氏试剂和3-三氟甲基苯基格氏试剂的方法。反应系统筛选工具（RSST）和差热分析（​​DTA）研究表明，这些三氟甲基苯基格氏试剂可在失去溶剂接触或适度加热的情况下爆炸。当按照本文所述的方法制备和处理时，这些格氏试剂可以安全地制备并用于高级中间体。