C-1-deuterated aldehydes are essential building blocks in the synthesis of deuterated chemicals and pharmaceuticals. This has led chemists to devise mild methodologies for their efficient production. Ideally, hydrogen–deuterium exchange (HDE) is the most effective approach. However, the traditional HDE for creating C-1-deuterated aldehydes often requires a complex system involving multiple catalysts and/or ligands. In this study, we present a mild photocatalytic HDE of the formyl C–H bond with D₂O. This process is facilitated by chlorine radicals that are generated in situ from low-cost FeCl₃. This strategy demonstrated a broad reaction scope and high functional group tolerance, affording good yields and ≤99% D incorporation. To bridge the gap between research and industrial applications, we designed a new flow photoreactor equipped with a high-intensity light-emitting diode bucket, enabling the synthesis of C-1-deuterated aldehydes on a scale of 85 g. Finally, we successfully produced several important deuterated aldehydes that are integral to the synthesis of deuterated pharmaceuticals.

中文翻译：

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通过氯自由基介导的甲酰基 C-H 键选择性氘化进行 C-1-氘代醛的光合作用

C-1-氘代醛是氘代化学品和药物合成中的重要组成部分。这促使化学家设计出温和的方法来实现高效生产。理想情况下，氢-氘交换（HDE）是最有效的方法。然而，用于生成 C-1-氘代醛的传统 HDE 通常需要涉及多种催化剂和/或配体的复杂系统。在本研究中，我们提出了甲酰基 C-H 键与 D ₂ O的温和光催化 HDE。该过程由低成本 FeCl ₃原位产生的氯自由基促进。该策略表现出广泛的反应范围和高官能团耐受性，提供良好的产率和 ≤99% D 掺入。为了弥合研究和工业应用之间的差距，我们设计了一种配备高强度发光二极管桶的新型流动光反应器，能够合成85克规模的C-1-氘代醛。最后，我们成功生产了几种重要的氘代醛，它们是氘代药物合成中不可或缺的一部分。