A Proton Conductive Porous Framework of an 18‐Crown‐6‐Ether Derivative Networked by Rigid Hydrogen Bonding Modules

• Published in: Angewandte Chemie International Edition Vol. 61; no. 45; pp. e202211686 - n/a
• Main Authors: Chen, Xin, Huang, Rui‐Kang, Takahashi, Kiyonori, Noro, Shin‐ichiro, Nakamura, Takayoshi, Hisaki, Ichiro
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 07.11.2022; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Carboxylic acids; Chemistry; Chemistry, Multidisciplinary; Crown Ether; Crystal Engineering; Hydrogen; Hydrogen Bond; Hydrogen bonding; Molecular structure; Physical Sciences; Porous Framework; Porous materials; Proton Conduction; Protons; Science & Technology; DESIGN; Proton Conduction; BONDED ORGANIC FRAMEWORKS; COMPLEXES; Crystal Engineering; CROWN-ETHERS; MOTIF; Hydrogen Bond; Crown Ether; Porous Framework
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202211686

A rigid hydrogen‐bonded organic framework (HOF) was constructed from a C3‐symmetric hexatopic carboxylic acid with a hydrophilic 18‐crown‐6‐ether (18C6) component. Despite the flexible macrocyclic structure with many conformations, the derivative with three 4,4’‐dicarboxy‐o‐terphenyl moieties in the periphery yielded a rigid layered porous framework through directional intermolecular hydrogen bonding. Interestingly, the HOF possesses 1D channels with bottleneck composed of 18C6 rings. The HOF shows proton conductivity (1.12×10−7 S cm−1) through Grotthuss mechanism (Ea=0.27 eV) under 98 %RH. The present unique water channel structure provides an inspiration to create molecular porous materials. A porous hydrogen‐bonded framework (HOF) was constructed from a 18‐crown‐6‐ether (18C6) derivative. Although a 18C6 macrocycle is flexible and has many possible conformations, directional intermolecular hydrogen bonds of 4,4′‐dicarboxy‐o‐terphenyl modules in the periphery of the 18C6 allowed to form a rigid HOF with 1D channels with a bottleneck composed of 18C6 rings. The wet HOF shows proton conductivity (1.12×10−7 S cm−1) through a Grotthuss mechanism (Ea=0.27 eV) under 98 %RH.