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1. Light‐Driven Hydrodefluorination of Electron‐Rich Aryl Fluorides by an Anionic Rhodium‐Gallium Photoredox Catalyst

   https://doi.org/10.1002/anie.202205575  

   Moore, James T.; Dorantes, Michael J.; Pengmei, Zihan; Schwartz, Timothy M.; Schaffner, Jacob; Apps, Samantha L.; Gaggioli, Carlo A.; Das, Ujjal; Gagliardi, Laura; Blank, David A.; et al (September 2022, Angewandte Chemie International Edition)

   Abstract An anionic Rh−Ga complex catalyzed the hydrodefluorination of challenging C−F bonds in electron‐rich aryl fluorides and trifluoromethylarenes when irradiated with violet light in the presence of H₂, a stoichiometric alkoxide base, and a crown‐ether additive. Based on theoretical calculations, the lowest unoccupied molecular orbital (LUMO), which is delocalized across both the Rh and Ga atoms, becomes singly occupied upon excitation, thereby poising the Rh−Ga complex for photoinduced single‐electron transfer (SET). Stoichiometric and control reactions support that the C−F activation is mediated by the excited anionic Rh−Ga complex. After SET, the proposed neutral Rh⁰intermediate was detected by EPR spectroscopy, which matched the spectrum of an independently synthesized sample. Deuterium‐labeling studies corroborate the generation of aryl radicals during catalysis and their subsequent hydrogen‐atom abstraction from the THF solvent to generate the hydrodefluorinated arene products. Altogether, the combined experimental and theoretical data support an unconventional bimetallic excitation that achieves the activation of strong C−F bonds and uses H₂and base as the terminal reductant. 

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2. Electronic effects of conjugated aryl groups on the properties and reactivities of di(arylethynyl)tetracenes

   https://doi.org/10.1039/d3ob01601c  

   Yan, Yu; Brega, Valentina; Pina, Manuel M; Thomas, Samuel W (January 2024, Organic & Biomolecular Chemistry)

   The electronic effects of different (hetero)aryl groups in di(arylethynyl)tetracenes substantially impact their optoelectronic properties and reactivity with singlet oxygen. 

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3. Ligand‐to‐Metal Charge Transfer of Ag(II) CF ₂ X Carboxylates: Quantum Yield and Electrophotocatalytic Arene Fluoroalkylation Tuned by X

   https://doi.org/10.1002/anie.202511642  

   Campbell, Brandon_M; Gordon, Jesse_B; Raguram, Elaine_Reichert; Reynolds, Kristopher_G; Sullivan, Meghan_G; Nocera, Daniel_G (September 2025, Angewandte Chemie International Edition)

   Abstract Incorporation of CF₂X groups beyond CF₃into arene scaffolds is underdeveloped despite these groups’ utility as halogen‐bond donors and as precursors to bioisosteres. Herein, we report the synthesis, characterization, and comparative photochemistry of a suite of [Ag(II)(bpy)₂O₂CCF₂X]⁺and Ag(II)(bpy)(O₂CCF₂X)₂(bpy = 2,2´‐bipyridine, X = F, CF₃, Cl, Br, H, CH₃) carboxylate complexes. We find a dramatic effect of the X substituent on the efficiency of generating CF₂X radicals by ligand‐to‐metal charge transfer (LMCT), with Ag(II) photoreduction rates varying by over an order of magnitude and quantum yields spanning over 20%. We provide insight into how electronic and structural perturbations of the Ag(II)–O₂CCF₂X core are manifested in the LMCT quantum efficiency. With this information in hand, Ag(II)‐mediated electrophotocatalytic CF₂X functionalization is carried out on a range of (hetero)arenes. This work expands the nascent field of Ag(II)‐based photocatalysis by allowing for (hetero)aryl–CF₂X functionalization directly from unactivated fluoroalkyl carboxylate precursors. 

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4. A free-radical design featuring an intramolecular migration for a synthetically versatile alkyl–(hetero)arylation of simple olefins

   https://doi.org/10.1039/D3SC06476J  

   Babcock, Dylan J; Wolfram, Andrew J; Barney, Jaxon L; Servagno, Santino M; Sharma, Ayush; Nacsa, Eric D (March 2024, Chemical Science)

   A free-radical approach featuring an intramolecular aryl migration has significantly expanded the scope for the alkyl–(hetero)arylation of simple olefins. It was also leveraged as the key step in a new synthesis of a recently approved pharmaceutical. 

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5. Photochemically Driven Nickel‐Catalyzed Carboxylative C−N Coupling: Scope and Mechanism

   https://doi.org/10.1002/chem.202301271  

   Abid, Seifallah; Quirion, Kevin P.; Yang, Yi; Tang, Renhe; Mai, Binh Khanh; Liu, Peng; Tlili, Anis (August 2023, Chemistry – A European Journal)

   Herein we disclosed an unprecedented photochemically driven nickel‐catalyzed carboxylative Buchwald–Hartwig amination to access a wide range of aryl carbamate derivatives. This reaction is performed under mild condition of temperature and atmospheric pressure of CO2 starting from commercially available (hetero)aryl iodides/bromides derivatives and alkyl amines preventing the formation of hazardous and/or toxic waste. Moreover, preliminary mechanistic investigations including stochiometric experiments as well as DFT calculations allow us to shed light on the reaction mechanism. 

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