A simple photocatalytic method was developed for the synthesis of unsymmetrical 1,2-diamines by the unprecedented reductive coupling of N-benzylidene-[1,1'-biphenyl]-2-amines with an aliphatic amine. The presence of a phenyl substituent in the aniline moiety of the substrate was critical for the reactivity. The reaction proceeded via radical–radical cross-coupling of α-amino radicals generated by proton-coupled single-electron transfer in the presence of an Ir photocatalyst. On the other hand, symmetrical 1,2-diamines were selectively produced from the same starting materials by the judicious choice of the reaction conditions, showcasing the distinct reactivity of N-benzylidene-[1,1'-biphenyl]-2-amines. The developed method can be employed for the synthesis of various bulky vicinal diamines, which are potential ligands in stereoselective synthesis.

中文翻译：

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N-亚苄基-[1,1'-联苯] -2-胺在光氧化还原条件下的独特反应性。

通过空前的N-亚苄基-[1,1'-联苯] -2-胺与脂肪胺的还原偶联，开发了一种简单的光催化方法，用于合成不对称的1,2-二胺。底物的苯胺部分中苯基取代基的存在对于反应性至关重要。该反应通过在Ir光催化剂存在下由质子偶联的单电子转移产生的α-氨基的自由基-自由基交叉偶联而进行。另一方面，通过明智地选择反应条件，可以从相同的原料中选择性地制备对称的1,2-二胺，这表明N具有独特的反应性-亚苄基-[1,1'-联苯] -2-胺。所开发的方法可用于合成各种笨重的邻位二胺，它们是立体选择性合成中的潜在配体。