Photoredox catalysis is an important development in organic synthesis, offering distinct reaction pathways under mild conditions. However, to date, most photocatalysts available to synthetic chemists are homogeneous metal complexes or organic dyes, which raise issues of cost, recyclability, and waste production. Here we report the discovery of a covalent triazine framework photocatalyst (CTF-2) for decarboxylative conjugate addition of a range of carboxylic acids under visible-light irradiation. The decarboxylation reaction can be coupled with a variety of other reactions, including metallaphotoredox arylation, alkylation, fluorination, and dehydrogenative aniline synthesis. CTF-2 can be prepared on a large scale and recycled without loss of catalytic efficiency for at least four cycles. To demonstrate application in pharmaceutical drug synthesis, we synthesized (±)-rolipram in five steps from isovanillin using a CTF-2-catalyzed decarboxylative conjugate addition as the key step.

中文翻译：

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使用高通量筛选发现用于可见光驱动化学合成的共价三嗪骨架光催化剂

光氧化还原催化是有机合成的重要发展，在温和条件下提供不同的反应途径。然而，迄今为止，合成化学家可用的大多数光催化剂都是均相金属络合物或有机染料，这会带来成本、可回收性和废物产生等问题。在这里，我们报告了一种共价三嗪骨架光催化剂 (CTF-2) 的发现，用于在可见光照射下对一系列羧酸进行脱羧共轭加成。脱羧反应可以与多种其他反应相结合，包括金属光氧化还原芳基化、烷基化、氟化和脱氢苯胺合成。CTF-2 可以大规模制备并循环使用，至少四次循环不会损失催化效率。为了证明在药物合成中的应用，