Metal‐Organic Framework Supported Copper Photoredox Catalysts for Iminyl Radical‐Mediated Reactions

Visible‐light copper photocatalysis has recently emerged as a viable technology for building sustainable synthetic processes. To broaden the applications of phosphine‐ligated copper(I) complexes, we describe herein an effective metal‐organic framework (MOF)‐supported copper(I) photocatalyst for multiple iminyl radical‐mediated reactions. Due to site isolation, the heterogenized copper photosensitizer has a significantly higher catalytic activity than its homogeneous counterpart. Using a hydroxamic acid linker to immobilize copper species on MOF supports affords the heterogeneous catalysts with high recyclability. The post‐synthetic modification sequence on MOF surfaces allows for the preparation of previously unavailable monomeric copper species. Our findings highlight the potential of using MOF‐based heterogeneous catalytic systems to address fundamental challenges in the development of synthetic methodologies and mechanistic investigations of transition‐metal photoredox catalysis. A binap‐ligated copper dimer has been heterogenized on a pillar‐layered MOF surface for the first time using a hydroxamic acid linker. This MOF‐supported dimeric copper photocatalyst demonstrates much higher activity and recyclability than its homogeneous counterparts in intra‐ and intermolecular radical reactions of N‐acyloxy imidates and O‐acyl oximes.