An efficient and versatile synthesis of 2,6-diiodobenzaldehydes via highly regioselective metal–iodine exchange (MIE) of 5-substituted 1,2,3-triiodobenzenes is reported. The nature of substituents (R) on the phenyl has a large influence on the reactivity of reaction but not on the regioselectivity. The regioselectivity of the MIE can be controlled by the use of ethyl formate as a formylating agent providing only the internal benzaldehyde derivatives in excellent site-selectivity. The best reactivity and the highest isolated yields were furnished with products bearing electron-rich substituents. Several chemical transformations of the target compound as a valuable precursor in synthesis were also demonstrated providing the desired derivatives in good isolated yields. This report discloses a protocol for the synthesis of 2,6-diiodobenzaldehyde derivatives that is scalable, general in scope, and indeed difficult to be made by other means.

中文翻译：

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温和、高效且高度区域选择性地合成 2,6-二碘苯甲醛衍生物

报道了通过 5-取代的 1,2,3-三碘苯的高区域选择性金属碘交换 (MIE) 高效且通用的合成 2,6-二碘苯甲醛。苯基上的取代基 (R) 的性质对反应的反应性有很大影响，但对区域选择性没有影响。MIE 的区域选择性可以通过使用甲酸乙酯作为甲酰化剂来控制，仅提供具有优异位点选择性的内部苯甲醛衍生物。最好的反应性和最高的分离产率是由带有富电子取代基的产品提供的。还证明了目标化合物作为合成中有价值的前体的几种化学转化，以良好的分离产率提供了所需的衍生物。本报告公开了合成 2 的方案，