Visible-light-driven aerobic oxidation via a dual ROS-generating manganese(II)-organic framework photocatalyst

Abstract

Developing sustainable and efficient photocatalytic systems for aerobic oxidation remains a pivotal challenge in green chemistry. Herein, we report the rational design and synthesis of a novel manganese(II)-organic framework (An-MnMOF) by integrating anthracene-based photoactive ligands with Mn(II)-oxo clusters. The framework exhibits broad visible-light absorption extending up to 650 nm, efficient charge separation, and dual reactive oxygen species (ROS) generation capabilities. Structural characterization confirms a crystalline 2D lamellar architecture with hierarchical porosity, while mechanistic studies reveal a synergistic interplay between anthracene-mediated light harvesting and Mn(II)-driven redox processes. Under visible-light irradiation, An-MnMOF achieves exceptional catalytic performance in aerobic oxidation reactions, including hydroxylation of arylboronic acids (＞95 % yield) and benzylic C(sp³)-H bond activation (＞85 % yield), outperforming the homogeneous Mn catalyst. The framework’s microporous channels stabilize reactive intermediates, suppressing overoxidation, while its robust chemical and thermal stability enables five consecutive recycling cycles without activity loss. This work establishes a paradigm for noble-metal-free photocatalysis by leveraging MOF-confined dual-function sites for solar-driven organic transformations, advancing sustainable synthesis methodologies.