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Boronic acids are centrally important functional motifs and synthetic precursors. Visible lightinduced borylation may provide access to structurally diverse boronates, but a broadly efficient photocatalytic borylation method that can effect borylation of a wide range of substrates, including strong C-O bonds, remains elusive. Herein, we report a general, metal-free visible light-induced photocatalytic borylation platform that enables borylation of electron rich derivatives of phenols and anilines, chloroarenes, as well as other haloarenes. The reaction exhibits excellent functional group tolerance, as demonstrated by the borylation of a range of structurally complex substrates. Remarkably, the reaction is catalyzed by phenothiazine, -a simple organic photocatalyst with MW<200 that mediates the previously unachievable visible light-induced single electron reduction of phenol derivatives with reduction potentials as negative as ~-3 V vs SCE by a proton-coupled electron transfer mechanism. Mechanistic studies point to the crucial role of the photocatalyst-base interaction.

Direct conversion of renewable biomass and bioderived chemicals to valuable synthetic intermediates for organic synthesis and materials science applications by means of mild and chemoselective catalytic methods has largely remained elusive. Development of artificial catalytic systems that are compatible with enzymatic reactions provides a synergistic solution to this enduring challenge by leveraging previously unachievable reactivity and selectivity modes. We report herein a dual catalytic dehydrodecarboxylation reaction that is enabled by a crossover of the photoinduced acridinecatalyzed O−H hydrogen atom transfer (HAT) and cobaloxime-catalyzed C−H-HAT processes. The reaction produces a variety of alkenes from readily available carboxylic acids. The reaction can be embedded in a scalable triple-catalytic cooperative chemoenzymatic lipase−acridine−cobaloxime process that allows for direct conversion of plant oils and biomass to long-chain terminal alkenes, precursors to bioderived polymers.

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The development of efficient and selective C À N bond-forming reactions from abundant feedstock chemicals remains acentral theme in organic chemistry owing to the key roles of amines in synthesis,d rug discovery,a nd materials science.H erein, we present ad ual catalytic system for the Nalkylation of diverse aromatic carbocyclic and heterocyclic amines directly with carboxylic acids,by-passing their preactivation as redox-active esters.The reaction, which is enabled by visible-light-driven, acridine-catalyzed decarboxylation, provides access to N-alkylated secondary and tertiary anilines and N-heterocycles.Additional examples,including double alkylation, the installation of metabolically robust deuterated methyl groups,a nd tandem ring formation, further demonstrate the potential of the direct decarboxylative alkylation( DDA) reaction.