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The difunctionalization of unsaturated bonds plays a vital role in the enrichment of molecular complexity. While various catalytic methods for alkene and alkyne difunctionalization have been developed in recent years, hetero‐functionalization the introduction of two different atoms has been less explored. This is mainly due to the challenges associated with achieving high chemo‐, regio‐, and stereoselectivity, especially when adding two similar atoms from the same group across unsaturated bonds. In this study, we describe a nickel‐catalyzed, three‐component reductive protocol for group 14 element hetero‐difunctionalization of 1,3‐enynes using electrochemistry. This new method is mild, selective, and general, allowing for the silyl‐, germanyl‐, and stannyl‐alkylation of enynes. Various chlorosilanes as well as chlorogermans, and chlorostannanes can be successfully used in combination with aryl/alkyl‐substituted 1,3‐enynes and primary, secondary, and tertiary alkyl bromides in the electroreductive coupling. [ABSTRACT FROM AUTHOR]

The peroxynitrite anion (ONOO−) is closely associated with many diseases and the creation of ONOO− donors is an essential means of understanding its pathophysiological functions. However, it is challenging to develop ONOO− donors due to the difficulties in simultaneously producing highly reactive and short‐lived nitric oxide (NO) and superoxide anion (O2⋅−). Here, we report a novel strategy for constructing ONOO− donors by combining near‐infrared (NIR)‐mediated type I photosensitization and photoredox catalysis. The key design using a Nile blue analogue that can serve as both a type I photosensitizer and a metal‐free photocatalyst. Intriguingly, the formation of O2⋅− via type I photosensitization avoids oxygen interference and instead activates nitrobenzofurazan‐based NO donors via oxygen‐tolerant NIR photoredox catalysis. The simultaneous release of O2⋅− and NO leads to ONOO− release, showing both antibacterial and antibiofilm activities. [ABSTRACT FROM AUTHOR]

The formation of C‐heteroatom bonds represents an important type of bond‐forming reaction in organic synthesis and often provides a fast and efficient access to privileged structures found in pharmaceuticals, agrochemical and materials. In contrast to conventional Pd‐ or Cu‐catalyzed C‐heteroatom cross‐couplings under high‐temperature conditions, recent advances in homo‐ and heterogeneous Ni‐catalyzed C‐heteroatom formations under mild conditions are particularly attractive from the standpoint of sustainability and practicability. The generation of NiIII and excited NiII intermediates facilitate the reductive elimination step to achieve mild cross‐couplings. This review provides an overview of the state‐of‐the‐art approaches for mild C‐heteroatom bond formations and highlights the developments in photoredox and nickel dual catalysis involving SET and energy transfer processes; photoexcited nickel catalysis; electro and nickel dual catalysis; heterogeneous photoredox and nickel dual catalysis involving graphitic carbon nitride (mpg‐CN), metal organic frameworks (MOFs) or semiconductor quantum dots (QDs); as well as more conventional zinc and nickel dual catalyzed reactions. [ABSTRACT FROM AUTHOR]