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A water-soluble metallo-supramolecular polymer MSP-f-6Np, which possesses a regular pore aperture of 1.4 nm, has been assembled from a structurally flexible naphthalene-appended [Ru(bipy)3]2+ complex and cucurbit[8]uril. As the first periodic metallo-supramolecular polymer formed by a flexible building block, MSP-f-6Np exhibits a hydrodynamic diameter of 122 and 164 nm at 0.1 and 2.0 mM of the monomer concentrations. Synchrotron small angle X-ray scattering experiments confirm that MSP-f-6Np possesses porosity periodicity in both the solution and solid states. Compared with a control, the new highly ordered porous system displays enhanced photocatalytic activity for the degradation of organic dyes.

Cubic metal-covalent-supramolecular organic framework (MCSOF-1) hybrid has been created from the reaction of two molecular components and subsequent co-assembly with cucurbit[8]uril (CB[8]) in water. In the presence of CB[8], [Ru(bpy)3]2+ -based acylhydrazine 1·2Cl reacted with aldehyde 2·Cl to quantitatively yield six-armed precursor 3·8Cl through the generation of MCSOF-1. MCSOF-1 combines the structural features of metal-, covalent- and supramolecular organic frameworks. Its periodicity in water and in the solid state was confirmed by synchrotron X-ray scattering and diffraction experiments. MCSOF-1 could enrich discrete anionic polyoxometalates (POMs), maintain periodicity in acidic medium, and remarkably facilitate visible light-induced electron transfer from its [Ru(bpy)3]2+ units to enriched POMs, leading to enhanced catalysis of the POMs for the reduction of proton to H2 in both aqueous (homogeneous) and organic (heterogeneous) media.

Enrichment of molecular photosensitizers and catalysts in a confined nanospace is conducive for photocatalytic reactions due to improved photoexcited electron transfer from photosensitizers to catalysts. Herein, the self-assembly of a highly stable 3D supramolecular organic framework from a rigid bipyridine-derived tetrahedral monomer and cucurbit[8]uril in water, and its efficient and simultaneous intake of both [Ru(bpy)3 ]2+ -based photosensitizers and various polyoxometalates, that can take place at very low loading, are reported. The enrichment substantially increases the apparent concentration of both photosensitizer and catalyst in the interior of the framework, which leads to a recyclable, homogeneous, visible light-driven photocatalytic system with 110-fold increase of the turnover number for the hydrogen evolution reaction.

Porous organic polymers (POPs) have attracted increasing attention and emerged as a new research area in polymer chemistry. During the past decade, the intense desirability for application in aqueous scenarios has spawned the development of a specific class of POPs, i.e., water-soluble or dispersible porous organic polymers (WS-POPs) that can allow the implementation of porosity-based functions in aqueous media. In this Tutorial Review, aiming at providing a practical guide to this area, we will discuss recent advances in the preparation of WS-POPs through covalent/dynamic covalent, coordination and supramolecular approaches. As a result of their intrinsic and well-defined porosity, diverse topological architectures as well as unique water-processable features, many water-soluble/dispersible POPs have been demonstrated to exhibit potential for various applications, which include drug, DNA and protein delivery, bioimaging, photocatalysis, explosive detection and membrane separation. We will also highlight the related function of the representative structures. Finally, we provide our perspective for the future research, with a focus on the development of new structures and biofunctions. [ABSTRACT FROM AUTHOR]

Solar‐to‐hydrogen conversion is a sustainable way of producing renewable fuels, yet the efficiency is limited by the poor photo‐induced charge‐carrier separation on electrode surface. Developing active and stable hydrogen evolution photocatalysts is challenging and entails intelligent material structure design and tailoring. Here, a novel water dispersible supramolecular metal organic framework (SMOF) is employed as a general and high‐performance platform to encapsulate CdS quantum dots (QDs) for achieving highly improved solar‐induced H2‐production activity. Particularly, the CdS QDs@SMOF heterostructure exhibits an excellent H2 generation activity of 49.4 µmol h−1 (TOF = 47.0/h), exceeding those of most reported heterogeneous metal organic frameworks‐based photocatalytic systems. Advanced characterizations disclose that the strong electrostatic interaction and light‐induced charge transfer between SMOF and CdS QDs, combined with the high surface area, water dispersible nature, and abundant reactive centers synergistically contribute to this distinguished photocatalytic performance. The work not only demonstrates the water dispersible SMOF can serve as a versatile and effective platform supporting semiconductor to boost the photocatalytic H2‐production performance without co‐catalysts, but also paves avenues to the design and synthesis of SMOF‐based heterostructures for general catalysis applications. [ABSTRACT FROM AUTHOR]

Two rigid porous organic polymers (Ir-POP-1 and Ir-POP-2) were prepared from the coupling reactions of tetraphenylmethane tetraborate and two [Ir(ppy)2(dtbbpy)]+-based bitopic linkers and applied as heterogeneous visible-light photocatalysts for organic transformations. Ir-POP-2 was found to exhibit high catalytic activity for a wide range of organic reactions, which include Smiles–Truce rearrangement of alkyliodides, desulfurative conjugate addition to Michael acceptors, and aerobic oxidations of sulfides and arylboronic acids. For all the transformations, Ir-POP-2 could achieve heterogeneous photocatalytic efficiency that rivals that of the homogeneous prototype iridium complexes. This remarkably high photocatalytic performance has been attributed to the large pore size of the conjugated backbone. The new heterogeneous photocatalyst was also highly stable to achieve good recyclability for all the studied reactions and could be reused eight to nineteen times. [ABSTRACT FROM AUTHOR]

We present the postmodification of a diamondoid 3D supramolecular organic framework (SOF) to append [Ru(BPY)3]2+ groups through the formation of a hydrazone bond. The resulting SOF works as an efficient recyclable heterogeneous catalyst for visible-light-induced reduction of aromatic azides to amines. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photosensitizers incorporated into tetrahedral monomer efficiently avoid the aggregation. • Photosensitizer incorporated SOF provides increased stability, regularity, and catalytic activity. • SOF as a visible light photoredox catalyst exhibits good recyclability. Due to the urgent demand for environmentally friendly synthetic methods, metal-free materials have gained increasing prominence in various photocatalytic organic transformations. The utilization of supramolecular organic frameworks (SOFs) as photocatalysts has gradually emerged in photo-induced organic reactions, which complements the widespread use of porous organic polymers and covalent organic frameworks. SOFs, which are constructed through noncovalent interactions, can function as heterogeneous catalysts due to their low solubility in typical organic solvents. The present study reports the application of a SOF for heterogeneous photocatalysis. A tetraphenylmethane-based monomer (TM) incorporating four 4,4′-(thiazolo[5,4- d ]thiazole-2,5-diyl)bis(1-methyl-1-pyridinium) units (MPT) has been synthesized and co-assemble with cucurbit[8]uril (CB[8]) to afford a photoactive three-dimensional supramolecular organic framework (TM-SOF) through the encapsulation of two MPT units by CB[8]. Various methods have been employed to characterize the optical and electronic properties of TM-SOF and reveal its exceptional light-absorbing properties that facilitate photoredox catalysis by generating reactive radical species. As a heterogeneous photocatalyst, TM-SOF efficiently catalyzes photoinduced reductive dichlorination of α-chloroacetophenones and acetylation of amines with thioacetate with high recyclability. Mechanistic studies were further conducted to reveal the effect of the framework on the photocatalytic efficiency of the MPT unit. [ABSTRACT FROM AUTHOR]