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Here, we report a general approach to the synthesis of the difluoroalkyl bicycloalkanes (CF2‐BCAs), as structural surrogates of aryl ketones and ethers. The chemistry is driven by a dihydrobenzoacridine photocatalyst, that engages in a catalytic electron‐donor acceptor (EDA) complex, or directly reduces the fluorinated substrate. These two convergent manifolds lead to the generation of the R‐CF2 radical, that reacts with the [1.1.1]‐ or [3.1.1.]‐propellane. The method is extremely general, and extendable to complex bioactive molecules (30 examples, up to 87 % yield). The structural features of the CF2‐BCP hybrid bioisostere were investigated by single crystal X‐ray. Finally, we synthesised a CF2‐BCP analogue of a Leukotriene A4 hydrolase inhibitor, replacing the original aryl ether motif. In silico docking studies indicated that this new analogue maintains the same arrangement within the enzyme pocket, profiling the use of the CF2‐BCA hybrid bioisostere in medicinal chemistry settings. [ABSTRACT FROM AUTHOR]

The article titled "Front Cover: Green Light-Responsive D-A-D Quinoxaline Emitters for Luminescent Solar Concentrators: Potential Integration in Agrivoltaic Systems" discusses the use of polymeric films doped with quinoxaline-based emitters for luminescent solar concentrators. These materials selectively absorb green light, which is non-productive for plant photosynthesis, making them suitable for integrating photovoltaic technologies in agricultural settings. The authors suggest that this approach can provide both clean energy and food simultaneously. The article is authored by Giulio Goti, Gianna Reginato, Carmen Coppola, Alessio Dessì, Daniele Franchi, Alessandro Mordini, Alberto Picchi, Andrea Pucci, Adalgisa Sinicropi, Lorenzo Zani, and Massimo Calamante. [Extracted from the article]

Herein, we report our study on the design and development of a novel photocarboxylation method. We have used an organic photoredox catalyst (PC, 4CzIPN) and differently substituted dihydropyridines (DHPs) in combination with an organic base (1,5,7-triazabicyclodec-5-ene, TBD) to access a proton-coupled electron transfer (PCET) based manifold. In depth mechanistic investigations merging experimental analysis (NMR, IR, cyclic voltammetry) and density-functional theory (DFT) calculations reveal the key activity of a H-bonding complex between the DHP and the base. The thermodynamic and kinetic benefits of the PCET mechanism allowed the implementation of a redox-neutral fixation process leading to synthetically relevant carboxylic acids (18 examples with isolated yields up to 75%) under very mild reaction conditions. Finally, diverse product manipulations were performed to demonstrate the synthetic versatility of the obtained products.

The synthesis of four membered heterocycles usually requires multi-step procedures and prefunctionalized reactants. A straightforward alternative is the photochemical [2+2]-heterocycloaddition between an alkene and a carbonyl derivative, conventionally based on the photoexcitation of this latter. However, this approach is limited by the absorption profile of the carbonyl, requiring in most of the cases the use of high-energy UV-light, that often results in undesired side reactions and/or the degradation of the reaction components. The development of new and milder visible light-driven [2+2]-heterocycloadditions is, therefore, highly desirable. In this Review, we highlight the most relevant achievements in the development of [2+2]-heterocycloadditions promoted by visible light, with a particular emphasis on the involved reaction mechanisms. The open challenges will also be discussed, suggesting new possible evolutions, and stimulating new methodological developments in the field., (© 2022 Wiley-VCH GmbH.)