Photocatalyzed enantiodivergent synthesis of homoallylic and carboxylic acids featuring heterodiaryl quaternary carbon stereocenters

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The synthesis of heterodiaryl-based quaternary stereocenters is a very challenging task in organic synthesis, especially in the creation of highly functional scaffolds. Tetrahedral, congested carbons centers bearing two different aryl moieties have great importance for structure−activity relationship (SAR) studies in pharmaceutical discovery programs. Their presence in biological active natural products makes them fundamental for the future development of new bioactive molecules. Up to now, their synthesis requires unsustainable methodologies that involve high cost, unfavourable step-economy and a negative waste profile features and need highly reactive compounds that only permit low functional groups tolerance. Moreover, the enantioselective synthesis of both product enantiomer requires the use of both catalyst enantiomers raising the cost of the process. Therefore, it is fundamental to develop a simple, scalable and environmentally friendly approach for the enantioselective synthesis of compounds comprising heterodiaryl-quaternary stereocenters and functionalized derivatives. The PEACE project aims to develop a novel photocatalyzed, enantiodivergent synthesis process leading to such heterodiarylated all-carbon stereocenters. The designed dual catalytic cycle of the PEACE project merges Pd and photoredox catalysis to promote the enantioselective construction of new sp3-sp2 carbon-carbon bonds resulting into products featuring a quaternary carbon stereocenter. The enantiodivergent strategy is based on a judicious choice of structurally modular reaction partners with switchable aryl groups. The combination of VCCs (vinyl,aryl-substituted cyclic carbonates) and a new aryl radical precursor offers an innovative enantiodivergent reaction pathway leading to challenging quaternary stereocenters creating impetus in the area of organic synthetic chemistry, and revolutionizing similar synthetic designs in the pharmaceutical industry.