Vitamin B 12 catalyzed atom transfer radical addition. ó, Jackowska, A., Radzewicz, K., Giedyk, M. Formation of C–C bonds by addition of free radicals to alkenes. Visible-light-mediated synthesis of amidyl radicals: transition-metal-free hydroamination and N-arylation reactions. Formal synthesis of (−)-Aphanorphine using sequential photomediated radical reactions of dithiocarbamates. A new method for the production of acyl radicals. Characterization of the nucleophilic reactivities of thiocarboxylate, dithiocarbonate and dithiocarbamate anions. Oxidation of hydroxycyclohexadienyl radical by metal ions. Spectroelectrochemistry of potassium ethylxanthate, bis(ethylxanthato)nickel(II) and tetraethylammonium tris(ethylxanthato)nickelate(II). New photoiniferters: respective role of the initiating and persistent radicals. Lalevée, J., Blanchard, N., El-Roz, M., Allonas, X. Experimental and calculated electrochemical potentials of common organic molecules for applications to single-electron redox chemistry. Decatungstate as an efficient photocatalyst in organic chemistry. Photoredox-mediated routes to radicals: the value of catalytic radical generation in synthetic methods development. Photoredox catalysis in organic chemistry. Catalysis of radical reactions: a radical chemistry perspective. On the trail of xanthates: some new chemistry from an old functional group. A convenient source of alkyl and acyl radicals. Invention of new reactions useful in the chemistry of natural products. New and improved methods for the radical decarboxylation of acids. A new method for the deoxygenation of secondary alcohols. Synthetic organic electrochemical methods since 2000: on the verge of a renaissance. & Studer, A.) (John Wiley & Sons, Weinheim, 2012). in Encyclopedia of Radicals in Chemistry, Biology and Materials, Vol 1 (eds Chatgilialoglu, C. Radicals: reactive intermediates with translational potential. (eds) Radicals in Organic Synthesis (Wiley-VCH, Weinheim, Germany, 2001). We also describe how the method’s mild reaction conditions and high functional group tolerance could be advantageous for developing C–C bond-forming reactions, for streamlining the preparation of a marketed drug, for the late-stage elaboration of biorelevant compounds and for enantioselective radical catalysis. This catalytic S N2-based strategy, which exploits a fundamental mechanistic process of ionic chemistry, grants access to open-shell intermediates from a variety of substrates that would be incompatible with or inert to classical radical-generating strategies. The resulting photon-absorbing intermediate affords radicals upon homolytic cleavage induced by visible light. We use a nucleophilic dithiocarbamate anion catalyst, adorned with a well-tailored chromophoric unit, to activate alkyl electrophiles via an S N2 pathway. Here, we disclose a photochemical catalytic approach that harnesses different physical properties of the substrate to form carbon radicals. Traditionally, generating radicals requires strategies that exploit the bond dissociation energy or the redox properties of the precursors. Chemists extensively use free radical reactivity for applications in organic synthesis, materials science, and life science.
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