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Abstract Carbosulfenylation of olefins represents an important class of reactions for the synthesis of structurally diverse organosulfur compounds. Previous studies typically yield 1,2‐regioselectivity. In the context of diversity‐oriented synthesis, accessing the regioreversed products is desirable, significantly broadening the scope of these reactions. In this study, we report a nickel‐catalyzed 2,1‐carbosulfenylation of trifluoromethyl‐ andgem‐difluoroalkenes, using free thiols and benzyl bromides as sulfur and carbon sources, respectively. The unusual regioselectivity observed is enabled by a “radical sorting” mechanism. The Ni catalyst activates benzyl bromide to generate a benzylic radical that undergoes hydrogen atom transfer (HAT) with the thiol to form a sulfur‐centered radical. The sulfur radical subsequently adds to the fluoroalkenes, resulting in an α‐fluoroalkyl C‐radical. This radical undergoes S_H2 with a Ni–CH₂Ar to form a C(sp³)─C(sp³) bond and quaternary center, ultimately producing valuable fluoroalkyl thioethers. Isotopic labeling experiments corroborate a hydrogen atom transfer (HAT) event within the working mechanism. 

Abstract Alkynyl amides play crucial roles in organic synthesis in the production of bioactive compounds and valuable heterocycles. Despite numerous studies on their synthesis, challenges persist due to the necessity of harsh or hazardous conditions and the use of costly or unstable reagents. Herein, we present a one‐pot method for the synthesis of all three bonds of the alkyne under transition‐metal‐free conditions. An important feature of this chemistry is the use of readily available feedstock chemicals, such as methyl esters and acetamides. This approach offers efficient access to a wide range of aryl and alkyl alkynyl amides and demonstrates excellent tolerance towards various functional groups in a sustainable and cost‐effective manner. 

Photocatalytic 1,2-HAT of N-centered radicals leads to C-centered α-amino radicals, with trapping by phosphine oxides to access α-amino phosphine oxides. Mechanistic experiments and DFT calculations support a 1,2-HAT pathway. 

Not AvailableAn unmet challenge in radical relay difunctionalization of alkenes is incorporation of two discrete transient radicals in a regiocontrolled manner under transition metal-free conditions. Current protocols typically rely on persistent radicals or organometallic surrogates to trap radical adducts, thereby suppressing the undesired reactions but limiting the diversity. The direct use of two transient radicals remains synthetically elusive. We present a visible-light photoredox catalyzed alkene dialkylation strategy via a kinetically guided conjugative radical-radical coupling. This transition-metal-free approach enables two direct C(sp3)−C(sp3) bond formations across the C=C double bond using alkyl and allyl or benzyl radicals. Mechanistic investigations reveal the radical nature of the process. The success of this approach hinges on kinetically controlled radical addition to alkene substrates and the steric protection of the resulting radical adducts. This mild and functional-group tolerant reaction exhibits broad substrate scope and tolerates structurally complex substrates, highlighting its potential for late-stage functionalization. 

The synthesis of enantioenriched aziridines is important for drug development due to their prevalence in bioactive molecules. Previous methods often use expensive catalysts, activated substrates, or show poor stereoselectivity. Herein,... 

Transition-metals bind arene π-systems, removing e⁻density and acidifying benzylic C–H’s. Main group metals achieve thisviacation–π interactions. Both interactions enable catalytic base-promoted selective C–H functionalization. 

Visible-light-driven N-centered radicals lead to C-centered α-amino radicals through rare net-1,2-HAT processes, with trapping by silyl enol ethers to access β-amido ketone derivatives.