Supramolecular metal-organic frameworks that display high homogeneous and heterogeneous photocatalytic activity for H2 production

Abstract

Self-assembly has a unique presence when it comes to creating complicated, ordered supramolecular architectures from simple components under mild conditions. Here, we describe a self-assembly strategy for the generation of the first homogeneous supramolecular metal-organic framework (SMOF-1) in water at room temperature from a hexaarmed [Ru(bpy)3]2+-based precursor and cucurbit[8]uril (CB[8]). The solution-phase periodicity of this cubic transition metal-cored supramolecular organic framework (MSOF) is confirmed by small-angle X-ray scattering and diffraction experiments, which, as supported by TEM imaging, is commensurate with the periodicity in the solid state. We further demonstrate that SMOF-1 adsorbs anionic Wells−Dawson-type polyoxometalates (WD-POMs) in a one-cage-one-guest manner to give WD-POM@SMOF-1 hybrid assemblies. Upon visible-light (500 nm) irradiation, such hybrids enable fast multi-electron injection from photosensitive [Ru(bpy)3]2+ units to redox-active WD-POM units, leading to efficient hydrogen production in aqueous media and in organic media. The demonstrated strategy opens the door for the development of new classes of liquid-phase and solid-phase ordered porous materials.

A mutually stabilized host-guest pair

“…5A, red trace) were recorded in MeCN. One of the two TPZ 3+ units in the complex pyrene ⊂ 3 6+ •6PF 6 − has a more negative reduction potential, i.e., −730 mV, compared to −635 mV in the case of empty cage. The implication is that the LUMO (lowest unoccupied molecular orbital) of TPZ 3+ is increased by 0.095 eV and that the compound becomes more difficult to reduce when it undergoes - interactions with a pyrene guest.…”

In Situ Loading and Delivery of Short Single- and Double-Stranded DNA by Supramolecular Organic Frameworks

“…Recently, we developed a general strategy for the generation of water-soluble, three-dimensional supramolecular organic frameworks (SOFs) from the coassembly of pre-organized multi-cationic monomers with cucurbit [8]uril (CB [8]). [32][33][34][35][36][37] As a family of selfassembled, water-soluble, porous polyelectrolytes, diamondoid SOFs were demonstrated to adsorb anionic guests and deliver adsorbed chemotherapeutic reagents, such as pemetrexed, into tumor cells. 38 Herein, we describe seven SOFs, with a pore size of approximately 2.0-2.2 nm, that can incorporate short single -or doublestranded (ss-or ds-) DNA (21,23, and 58 nt) in a facile manner by simply mixing the two species together and deliver the DNA strands into noncancerous and cancerous cells.…”

2:2 Complexes from Diphenylpyridiniums and Cucurbit[8]uril: Encapsulation‐Promoted Dimerization of Electrostatically Repulsing Pyridiniums

“…Compound G1 was prepared through the methylation of 1 [10] in 70 %y ield (Scheme1). For the preparation of G2 (Scheme1), acid 2 was first treated with thionyl chloridet o afford the corresponding acyl chloride and then reactedw ith 3 in dichloromethane to produce 4 in 65 %y ield.…”

“…Finally,m ethylation of 8 in DMF,f ollowed by ion exchange, produced G2 in 70 %y ield. Derivative G3 wasp repared according to am ethod reportedi nt he literature, [10] and G4 and G5 were both obtained in 90 %y ield through the methylation of 4 or 5 in DMF.…”