A Robust Nickel‐Interlocked π‐Conjugated Covalent Organic Framework Catalyst for Photocatalytic Aromatic Finkelstein and retro‐Finkelstein Reactions

Covalent organic frameworks (COFs) are emerging as a versatile class of hosts for heterogeneous photocatalysis. Herein, we present a nickel‐decorated pyrene‐ and bipyridine‐based olefin‐linked COF ( Ni@COF1 ) as a robust and recyclable catalyst for visible‐light‐driven aromatic Finkelstein and retro‐Finkelstein reactions. The extended π‐conjugation within the COF framework enhances light absorption, promotes charge transport, and facilitates in situ Ni(0) generation from the pre‐installed Ni(II) centers. Compared to its reduced counterpart ( Ni@COF1R ), Ni@COF1 exhibits remarkable catalytic performance. The methodology enables selective halide exchange, broad functional group compatibility, and late‐stage diversification of eight bioactive molecules and nine pharmaceutical motifs. Furthermore, a gram‐scale reaction with batch and continuous flow conditions underscores its scalability and synthetic utility. The catalyst is robust and recycled five times without any loss of catalytic activity, reaching a total turnover number >850. These results highlight the significance of olefin‐linked COFs in advancing sustainable photocatalysis and expanding their role in fine chemical synthesis.