Electrophilic aromatic bromination using N-bromosuccinimide (NBS) is the most widely used reaction to synthesize highly functionalized aromatic compounds. We encountered catalytic activity of triphenylphosphine for aromatic bromination. This catalytic activity was successfully applied to a wide range of organic solvents and enabled the addition of NBS below the flash point of various organic solvents. Toward the industrial implementation of this bromination, we evaluated the process safety including the reaction heat and thermal decomposition. The analysis revealed that the characteristic behavior of the reaction heat made it difficult to suppress the increase of the internal temperature. However, precise evaluation of the reaction heat suggested the sequential addition of NBS. This procedure suppressed the increase of the internal temperature below 5 °C, which made the industrial implementation of this bromination feasible with process safety.

中文翻译：

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使用正溴琥珀酰亚胺制备三苯基膦进行亲电芳香族溴化反应的催化活性和工艺安全性评价


使用 N-溴琥珀酰亚胺 （NBS） 的亲电芳香族溴化是合成高度官能化芳香族化合物的最广泛使用的反应。我们遇到了三苯基膦对芳香族溴化的催化活性。这种催化活性成功地应用于多种有机溶剂，并能够在各种有机溶剂的闪点以下添加 NBS。为了实现这种溴化的工业化应用，我们评估了包括反应、热和热分解在内的工艺安全性。分析表明，反应热的特征行为使其难以抑制内部温度的升高。然而，对反应热的精确评估表明 NBS 的连续添加。该程序抑制了内部温度升高到 5 °C 以下，这使得这种溴化的工业实施在过程安全的情况下成为可能。