Structural reorganization in a hydrogen-bonded organic framework

Abstract

Self-recognition of 3,3′,5,5′-azobenzenetetracarboxylic acid yields a grid-like anionic hydrogen-bonded framework capable of undergoing structural reorganization by recrystallization in the presence of guanidinium cations.

Effect of Isomorphic Metal Substitution on the Fenton and Photo-Fenton Degradation of Methylene Blue Using Fe-Based Metal–Organic Frameworks

“…H 4 ABTC was synthesized according to a previously reported method . In a typical procedure, 5-nitroisophthalic acid (19 g) and sodium hydroxide (50 g) were suspended in 250 mL of ultrapure water purified using a Milli-Q Water Ultrapure Water System and reacted at 60°C with continuous stirring for 1 h. Next, glucose (100 g) was dissolved in 100 mL of warm ultrapure water, and the resulting solution was added dropwise to the yellow slurry that became dark brown as the nitro groups were reduced.…”

“…16,29−31 To evaluate the effects of different metals on the Fenton and photo-Fenton reaction rates, as well as the viability of PCN-250 as a heterogenous catalyst, a series of mixed-metal MOFs named PCN-250(Fe 2 M) (M = Ni, Co, Mn, and Fe) were synthesized and their viability as Fenton and photo-Fenton catalysts for the degradation of methylene blue was tested. 32 In a typical procedure, 5nitroisophthalic acid (19 g) and sodium hydroxide (50 g) were suspended in 250 mL of ultrapure water purified using a Milli-Q Water Ultrapure Water System and reacted at 60°C with continuous stirring for 1 h. Next, glucose (100 g) was dissolved in 100 mL of warm ultrapure water, and the resulting solution was added dropwise to the yellow slurry that became dark brown as the nitro groups were reduced. The mixture was allowed to cool down for 30 min, followed by exposure to a bubbling air stream for 16 h with continuous stirring at room temperature.…”

Organoboron Derivatives of Stereoregular Phenylcyclosilsesquioxanes

“…Each of these supramolecular classes offers promise for various applications . In this study, we focus on the precursors for producing HOFs because such systems are capable of reversible structure reorganization, which allows one to obtain materials that are sensitive to external effects, which, in turn, is relevant for the creation of smart materials …”

“…[9][10][11][12][13][14][15] In this study,w ef ocus on the precursors for producing HOFs because such systems are capable of reversible structure reorganization,w hich allows one to obtain materials that are sensitive to external effects, which, in turn, is relevant for the creationo fs mart materials. [16,17] The search for new chemicalc ompounds exhibiting specific interactions is an important task. Its solution would allow one to obtain materials with specified physicalp ropertiest hat can change dependingo nc ertaine xternal effects.…”

Two Hydrogen-Bonded Organic Frameworks with Imidazole Encapsulation: Synthesis and Proton Conductivity

“…Compared with MOFs and COFs, HOFs are formed through the interaction of hydrogen-bonding forces. − HOFs have high proton conductivity but poor stability for the weak hydrogen bonds. − Therefore, this shortcoming limits their use under high-temperature conditions. Selective introduction of guest molecules , can increase the number of hydrogen bonds and the stabilities of HOFs. − The large number of hydrogen-bond networks inside HOFs play a key role in the stability of the structure and proton conduction. − Therefore, it is particularly important to improve the proton conduction characteristics and stabilities of these materials. − …”