Tetrameric H-shaped assemblies as a motif in inclusion crystals of bent-shaped host molecules having nitrophenol moieties

Abstract

Bent-shaped compounds are attractive building blocks because they self-assemble into unique two- or three-dimensional structures. We used bent-shaped host molecule (1), which is composed of two nitrophenols linked to adamantane. Vapor diffusion of hexane into a tetrahydrofuran solution of 1 afforded inclusion crystals. The host molecules were assembled into tetrameric H-shaped structures as a motif through the quadruple π-stacking of nitrophenol moieties within a unit cell, in which eight hydroxy groups interacted with eight guests through hydrogen bonds. These assemblies were fabricated to form network structures with channels. In inclusion crystals with 1,4-dioxane, 1 was arranged into layer architectures that were packed into the channel structures. In inclusion crystals with γ-butyrolactone, 1 was aligned into network structures with channels, where cyclic dimeric structures without cavities were formed. These results demonstrate the crucial role of solvent molecules in the creation of tetrameric and dimeric motifs in the crystalline state.