Porous Pyrene Organic Cage with Unusual Absorption Bathochromic-Shift Enables Visible Light Photocatalysis

We have constructed a novel porous pyrene-based organic cage, PyTC1, through the condensation reaction of cyclohexanediamine with 5,5'-(pyrene-1,6-diyl) diisophthalaldehyde. Single-crystal X-ray diffraction analysis reveals the effective intercage C-H-n interaction between cyclohexanediimine and pyrene segments. Such a soft intercage C-H center dot center dot center dot pi interaction, rather than a classic J-aggregate with slipped pi-pi-stacking configuration, induced an unusual bathochromic shift of pyrene-based chromophore absorption from an ultraviolet region of PyTC1 in solution to the visible light region of PyTC1 in solid-state. This enabled heterogeneous visible light photocatalysis of aerobic hydroxylation of benzeneboronic acid derivatives. To the best of our knowledge, this is the first report that represents an absorption bathochromic shift caused by C-H center dot center dot center dot pi interaction. Such phenomenon could endow visible-light-driven photocatalysis that originally could only be achieved using UV light with the same chromophore. [GRAPHICS] .