Enhanced Reactivity for Aromatic Bromination via Halogen Bonding with Lactic Acid Derivatives
Enhanced Reactivity for Aromatic Bromination via Halogen Bonding with Lactic Acid Derivatives
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DOI：
10.1021/acs.joc.2c00611
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发表时间：
2022-06-16
影响因子：
3.6
通讯作者：
Baxter, Ryan D.
中科院分区：
文献类型：
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作者：
Baker, Sarah I.;Yaghoubi, Mahshid;Baxter, Ryan D.
我们报告了一种使用乳酸衍生物作为卤素键受体与 N-溴代琥珀酰亚胺 (NBS) 进行区域选择性芳香族溴化的新方法。乳酸的几种结构类似物可能通过路易斯酸/碱卤素键相互作用影响芳香族溴化的效率。芳香族溴化的速率比较表明，通过具有卤素键合能力的催化添加剂可以增强反应性。计算结果表明，路易斯碱性添加剂与 NBS 相互作用，在亲电转移之前增加溴的正电特性。开发了一种在室温水性条件下使用催化扁桃酸的优化程序，以促进各种芳烃底物上的芳香族溴化，并具有完全的区域选择性。
We report a new method for regioselective aromatic bromination using lactic acid derivatives as halogen bond acceptors with N-bromosuccinimide (NBS). Several structural analogues of lactic acid affect the efficiency of aromatic brominations, presumably via Lewis acid/base halogen-bonding interactions. Rate comparisons of aromatic brominations demonstrate the reactivity enhancement available via catalytic additives capable of halogen bonding. Computational results demonstrate that Lewis basic additives interact with NBS to increase the electropositive character of bromine prior to electrophilic transfer. An optimized procedure using catalytic mandelic acid under aqueous conditions at room temperature was developed to promote aromatic bromination on a variety of arene substrates with complete regioselectivity.