Light-driven fast and selective hydrogenation of nitroarenes with [Pt(N^N)]-polyoxometalate

The reduction of nitroaromatic compounds into their corresponding amines represents a crucial step in the bulk chemicals industry for the production of fine chemicals. Conventional thermal catalytic hydrogenation methods typically necessitate the use of external hydrogen sources and operate under stringent conditions, which often result in side reactions such as the undesired reduction of unsaturated functional groups and dehalogenation. In this study, we introduce an innovative photocatalytic system that integrates a covalently linked Pt(N^N)Cl₂-polyoxometalate catalyst electrostatically coupled with a cationic Ir-photosensitizer. This assembly demonstrates rapid and highly selective hydrogenation of nitroarenes by promoting efficient charge separation and transfer. Ultrafast transient absorption spectroscopy, emission quenching analysis, and time-resolved fluorescence measurement elucidate the mechanistic foundation of the enhanced catalytic activity, thereby underscoring the promise of metal catalyst-linked polyoxometalate for advanced photocatalytic chemical synthesis.