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Photo‐catalysis by small‐molecules is often limited by catalyst degradation and low electron‐transfer efficiency. Herein we report a stable N‐phenyl‐phenothiazine (PTH)‐derived porous coordination cage (PCC) as a highly efficient photocatalyst. By the incorporation of the photocatalytic PTH moiety into a PCC, aggregation‐induced quenching (AIQ) was shown to be reduced. An improvement in catalyst stability was discovered, ascribed to the synergistic effects of the PTH moieties. The catalyst, operating through a photolytic single‐electron transfer, was utilized for photo‐catalyzed dehalogenation and borylation. Evaluation of the catalytic mechanism in the borylation reaction showed that the improved performance results from the more efficient formation of the electron donor‐acceptor (EDA) complex with the cage. This discovery provides a potential strategy to improve the photophysical properties and stabilities of small‐molecule organic photocatalysts via supramolecular chemistry. [ABSTRACT FROM AUTHOR]

Photo‐catalysis by small‐molecules is often limited by catalyst degradation and low electron‐transfer efficiency. Herein we report a stable N‐phenyl‐phenothiazine (PTH)‐derived porous coordination cage (PCC) as a highly efficient photocatalyst. By the incorporation of the photocatalytic PTH moiety into a PCC, aggregation‐induced quenching (AIQ) was shown to be reduced. An improvement in catalyst stability was discovered, ascribed to the synergistic effects of the PTH moieties. The catalyst, operating through a photolytic single‐electron transfer, was utilized for photo‐catalyzed dehalogenation and borylation. Evaluation of the catalytic mechanism in the borylation reaction showed that the improved performance results from the more efficient formation of the electron donor‐acceptor (EDA) complex with the cage. This discovery provides a potential strategy to improve the photophysical properties and stabilities of small‐molecule organic photocatalysts via supramolecular chemistry. [ABSTRACT FROM AUTHOR]

A layered crystalline phosphate, α-Sn(HPO 4) 2 ·H 2 O, treated with CD 3 OD was characterized by the 31P, 119Sn, 1H and 2H solid-state NMR techniques. The 2H solid-echo MAS NMR spectra of the product have unexpectedly revealed deuterated hydronium ions on the surface of this material instead of intercalated methanol. According to the 13C NMR and GC–MS studies, these ions are formed by water molecules following a dehydration of the methanol‑ d 4 to yield deuterated dimethyl ether. [Display omitted] A layered crystalline phosphate, α-Sn(HPO 4) 2 ·H 2 O, treated with CD 3 OD was characterized by the 31P, 119Sn, 1H and 2H solid-state NMR techniques. The 2H solid-echo MAS NMR spectra of the product have unexpectedly revealed deuterated hydronium ions on the surface of this material instead of intercalated methanol. According to the 13C NMR and GC–MS studies, these ions are formed by water molecules following a dehydration of the methanol‑ d 4 to yield deuterated dimethyl ether. [ABSTRACT FROM AUTHOR]

Enzymatic catalysis has fueled considerable interest from chemists due to its high efficiency and selectivity. However, the structural complexity and vulnerability hamper the application potentials of enzymes. Driven by the practical demand for chemical conversion, there is a long-sought quest for bioinspired catalysts reproducing and even surpassing the functions of natural enzymes. As nanoporous materials with high surface areas and crystallinity, metal–organic frameworks (MOFs) represent an exquisite case of how natural enzymes and their active sites are integrated into porous solids, affording bioinspired heterogeneous catalysts with superior stability and customizable structures. In this review, we comprehensively summarize the advances of bioinspired MOFs for catalysis, discuss the design principle of various MOF-based catalysts, such as MOF–enzyme composites and MOFs embedded with active sites, and explore the utility of these catalysts in different reactions. The advantages of MOFs as enzyme mimetics are also highlighted, including confinement, templating effects, and functionality, in comparison with homogeneous supramolecular catalysts. A perspective is provided to discuss potential solutions addressing current challenges in MOF catalysis. [ABSTRACT FROM AUTHOR]