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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]

N‐Fused heterocycles are of particular use and upmost importance in multiple fields. Herein, we disclose a conceptually new approach for the rapid assembly of N‐fused heteroarenes from alkenes. A portfolio of strategically designed heterocyclization reagents are readily prepared for the cascade reaction. A plethora of N‐fused heteroarenes including seven types of heterocyclic core are furnished. The protocol features a broad functional‐group compatibility and high product diversity, and provides a practical tool for late‐stage heteroarene elaboration. [ABSTRACT FROM AUTHOR]

Chemical transformations based on cascade reactions have the potential to simplify the preparation of diverse and architecturally complex molecules dramatically. Herein, we disclose an unprecedented and efficient method for the cross‐coupling of radical precursors, dienes, and electrophilic coupling partners via a photoredox‐ and nickel‐enabled cascade cross‐coupling process. The cascade reaction furnishes a diverse array of saturated carbo‐ and heterocyclic scaffolds, thus providing access to a quick gain in C−C bond saturation. [ABSTRACT FROM AUTHOR]

Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds is of great synthetic value. Despite advances in radical‐mediated functionalization of C(sp3)−H bonds by a hydrogen‐atom transfer process, the site‐selective vinylation of remote C(sp3)−H bonds still remains underexplored. Reported herein is a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds. The remote C(sp3)−H activation is promoted by a C‐centered radical instead of the commonly used N and O radicals. The reaction possesses high product diversity and synthetic efficiency, furnishing a plethora of synthetically valuable E alkenes bearing tri‐/di‐/mono‐fluoromethyl and perfluoroalkyl groups. Give and take: Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds remains challenging. Herein a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds is reported. The activation of a remote C(sp3)−H bond is promoted by a C‐centered radical instead of the commonly used N and O radicals. [ABSTRACT FROM AUTHOR]

Abstract: Reported for the first time is a tertiary‐alcohol‐guided heteroarylation of remote C(sp3)−H bonds. The mild and direct generation of alkoxyl radicals from alcohols is enabled by visible‐light photocatalysis. A remote hydrogen atom and heteroaryl migration sequence are involved in the reaction. Many sensitive groups remain intact in the reaction, thus illustrating wide functional‐group compatibility. This protocol provides a practical strategy for the late‐stage modification of alkyl ketones. [ABSTRACT FROM AUTHOR]

The first iridium-catalyzed intermolecular cyclization between alkynes and ring-fused benzocyclobutenols (RBCB) through C−C bond cleavage is described. A variety of elusive polycyclic aromatic hydrocarbons (PAHs) with multiple substituents are obtained in good yields under mild conditions. This procedure provides a unique and expeditious tool for the synthesis of PAHs. [ABSTRACT FROM AUTHOR]