A Hydrogen-Bonded, Hexagonally Networked, Layered Framework with Large Aperture Designed by Structural Synchronization of a Macrocycle and Supramolecular Synthon

To develop porous organic frameworks,
precise control of the stacking
manner of two-dimensional porous motifs and structural characterization
of the resultant framework are important. From these points of view,
porous molecular crystals formed through reversible intermolecular
hydrogen bonds, such as hydrogen-bonded organic frameworks (HOFs),
can provide deep insight because of their high crystallinity, affording
single-crystalline X-ray diffraction analysis. In this study, we demonstrate
that the stacking manner of hydrogen-bonded hexagonal network (HexNet)
sheets can be controlled by synchronizing a homological triangular
macrocyclic tecton and a hydrogen-bonded cyclic supramolecular synthon
called the phenylene triangle. A structure of the resultant HOF was
crystallographically characterized and revealed to have a large channel
aperture of 2.4 nm. The HOF also shows thermal stability up to 290
°C, which is higher than that of the conventional HexNet frameworks.

为构建多孔有机框架，对二维多孔基元的堆叠方式以及所得框架的结构表征至关重要。从这些角度出发，通过可逆的分子间氢键形成的多孔分子晶体，如氢键有机框架（HOFs），由于其高结晶度，能够提供深刻的洞察，并允许进行单晶X射线衍射分析。在本研究中，我们展示了一种通过同步同伦三角大环结构（同伦三角大环结构）和称为苯环三角的氢键超分子合成子，可以控制氢键六方网络（HexNet）片层的堆叠方式。所得HOF的结构经过晶体学表征，显示其具有2.4纳米的大通道开口。此外，该HOF还表现出高达290°C的热稳定性，这一稳定性高于传统的HexNet框架。