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  1. Allyl carboxylates are useful synthetic intermediates in a variety of organic transformations, including catalytic nucleophilic/electrophilic allylic substitution reactions and 1,2-difunctionalization reactions. However, the catalytic 1,3-difunctionalization of allyl carboxylates remains elusive. Herein, we report the first photoinduced, phosphine-catalyzed 1,3-carbobromination of allyl carboxylates, affording a range of valuable substituted isopropyl carboxylates (sIPC). The transformation has broad functional group tolerance, is amenable to the late-stage modification of complex molecules and gram-scale synthesis, and expands the reaction profiles of allyl carboxylates and phosphine catalysis. Preliminary experimental and computational studies suggest a non-chain-radical mechanism involving the formation of an electron donor–acceptor complex, 1,2-radical migration (RaM), and Br-atom transfer processes. We anticipate that the 1,2-RaM reactivity of allyl carboxylates and the phosphine-catalyzed radical reaction will both serve as a platform for the development of new transformations in organic synthesis. 
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  2. null (Ed.)
    Excited-state catalysis, a process that involves one or more excited catalytic species, has emerged as a powerful tool in organic synthesis because it allows access to the excited-state reaction landscape for the discovery of novel chemical reactivity. Herein, we report the first excited-state palladium-catalyzed 1,2-spin-center shift reaction that enables site-selective functionalization of carbohydrates. The strategy features mild reaction conditions with high levels of regio- and stereoselectivity that tolerate a wide range of functional groups and complex molecular architectures. Mechanistic studies suggest a radical mechanism involving the formation of hybrid palladium species that undergoes a 1,2-spin-center shift followed by the reduction, deuteration, and iodination to afford functionalized 2-deoxy sugars. The new reactivity will provide a general approach for the rapid generation of natural and unnatural carbohydrates. 
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  3. The organic photocatalyst (9-mesityl-10-methylacridinum tetrafluoroborate) in the presence of visible light is used to initiate thiol–ene and thiol–yne reactions. Thiyl radicals are generated upon quenching the photoexcited catalyst with a range of thiols. The highlighted mild nature of the reaction conditions allows a broad substrate scope of the reactants. Relying on this efficient metal-free condition, both thiol–ene and thiol–yne reactions between carbohydrates and peptides could be realized in excellent yields. 
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  4. Abstract

    The development of photocatalytic intermolecular hydroamination reaction between N‐aminated dihydropyridines and unactivated alkenes is reported. Metal‐free co‐catalysts, rhodamine 6G and thiophenol, in presence of visible light are used to initiate the process. The transformation shows a broad substrate scope, both alkenes and amidyl radical can act as coupling partners. The radical strategy provides excellent anti‐Markovnikov selectivity and regioselectivity in diene substrates.

     
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