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.