Hydrogen bonded frameworks: smart materials used smartly

Abstract

Hydrogen-bonded host frameworks constructed from carefully selected molecular building blocks can exhibit architectures capable of encapsulating a wide range of guest molecules, with promising opportunities in key technologies.

Design Rules of Hydrogen-Bonded Organic Frameworks with High Chemical and Thermal Stabilities

“…These G-S -type HOFs exhibited permanent porosity under gas sorption and were recently used as host crystals to include a diverse range of unknown guests for their targeted single-crystal structure determinations (Figure ). , …”

“…284 These G-S-type HOFs exhibited permanent porosity under gas sorption 285 and were recently used as host crystals to include a diverse range of unknown guests for their targeted single-crystal structure determinations (Figure 17). 45,276 Inspired by Ward's groundbreaking work on guanidiniumsulfonate frameworks, White et al proposed that the interactions between tetratopic amidinium-containing receptors with terephthalate anions can form framework materials assembled through charge-assisted H-bonds. For example, they reported that tetraamidinium cations and dicarboxylate anions could be combined to form nine diamondoid crystalline porous frameworks connected via H-bonding interactions.…”

“…In addition to MOFs and COFs, hydrogen-bonded organic frameworks (HOFs), which are self-assembled from pre-designed and discrete molecular tectons with intermolecular hydrogen bonds, have recently emerged as a novel library of functional crystalline porous materials. − Owing to the reversible and flexible nature of H-bonds, HOFs display environmentally friendly preparation strategies under relatively mild conditions, easy regeneration and purification, metal-free biocompatibility, self-adaptive structure transformation, solution processability, and recyclability . The successful preparation of a stable HOF, tecton-1 ( L2 ), in 1997 by Wuest led to a rapid expansion of experimental and theoretical investigations in this field .…”

Heterocyclic compounds bearing s-triazine and cyclotriphosphazene scaffolds: facile synthesis, hydrogen-bonded organic framework construction and fluorescent amine sensing

“…2,10 Furthermore, such molecules usually contain N, O, and P elements as hydrogen bonding sites, which can easily generate various non-covalent interactions, such as intermolecular hydrogen bonds, which then tend to form organic crystals with a definite and highly ordered molecular packing structure. 11,12 This can not only provide a model for exploring the "structure-property" relationship but also can tune the photophysical properties to achieve different optical functions. Therefore, it is important to synthesize heterocyclic compounds bearing s-triazine and cyclotriphosphazene scaffolds and develop their solid crystals through non-covalent interactions between molecules.…”

Enabling Technology for Supramolecular Chemistry

“…Huge progress has been made in the function, selectivity, and efficiency of artificial supramolecular systems. The diversity of materials and structures, including those that exploit mechanical bonds [catenanes ( Gil-Ramírez et al, 2015 ), rotaxanes ( Yang et al, 2019 ), knots ( Fielden et al, 2017 )], host-guest interactions [macrocycle ( Liu et al, 2017 ), cage structures ( Hasell and Cooper, 2016 )], and framework or soft materials [metal-organic frameworks (MOFs) ( Zhou and Kitagawa, 2014 ; Jiao et al, 2019 ), hydrogen-bonded organic frameworks (HOFs) ( Yusov et al, 2021 ), supramolecular polymers ( Yang et al, 2015 ) and gels ( Weiss, 2014 )], is ever-increasing, as is our ability to design and use these structures. As such, promising applications are emerging: porous supramolecular materials have potential in carbon capture ( Huck et al, 2014 ), self-healing polymers could produce materials with enhanced recyclability ( Song et al, 2019 ), and glucose binders could transform how diabetes is managed ( Tromans et al, 2019 ), to name just a few.…”