A 3D Anionic Metal Covalent Organic Framework with soc Topology Built from an Octahedral Ti^IV Complex for Photocatalytic Reactions

The construction of three-dimensional (3D) covalent organic frameworks (COFs) remains challenging due to the limited types of organic building blocks. With octahedral Ti^IV complex as the building unit, this study reports on the first 3D anionic titanium-based COF (Ti-COF-1) with an edge-transitive (6, 4)-connected soc topology. Ti-COF-1 exhibits high crystallinity, superior stability, and large specific surface area (1000.4 m² g^-1 ). Moreover, Ti-COF-1 has a broad absorption band in the UV spectrum with an optical energy gap of 1.86 eV, and exhibits high photocatalytic activity toward Meerwein addition reactions. This research demonstrates an attractive strategy for the design of 3D functional COFs.