An efficient and convenient method with wide applicability for the synthesis of C2-tetrasubstituted indolin-3-ones via copper-catalyzed redox cycloisomerization of nonprefunctionalized nitroalkynes has been developed. This protocol features simple operation, readily available starting materials, good functional group tolerance, broad scope, and diboron as the reductant.

中文翻译：

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铜催化的硝基二氟烷基化和硝基炔的氧化还原环化反应，用于构建C2-四取代的吲哚-3-酮。

通过铜的非预官能化硝基炔烃的氧化还原环异构化合成C2-四取代的吲哚-3-酮的一种有效，方便的方法，具有广泛的适用性。该方案的特点是操作简单，原料易得，官能团耐受性好，适用范围广，并且乙硼烷可作为还原剂。