Guest⊂Guest⊂Host Multicomponent Molecular Crystals: Entrapment of Guest⊂Guest in Honeycomb Networks Formed by Self-Assembly of 1,3,5-Tri(4-hydroxyaryl)benzenes

摘要

Sterically-engineered rigid trigonal molecular modules based on 1,3,5-tri(4-hydroxyphenyl)benzenes H1 and H2 undergo O-HO hydrogen-bonded self-assembly into eight-fold catenated hexagonal (6,3) and two-fold interpenetrated undulated square (4,4) networks, respectively. In the presence of [18]crown-6 as a guest, the triphenol H1 is found to self-assemble into a honeycomb network with hexagonal voids created between three triphenol building blocks. The guest [18]crown-6 molecules are found to be nicely nested in hexagonal enclosures. The empty spaces within the crowns can be further filled with neutral (MeOH/water, MeOH/MeNO₂) or ionic guest species such as KI/KAcAc to furnish novel multicomponent assemblies, that is, guest⊂guest⊂host, that typify Russian dolls. In contrast, triphenol H2 is found to yield analogous multicomponent molecular crystals in which the guest crown–K+ acts as a spacers in the hydrogen-bonded self-assembly that leads to distorted chicken wire networks.