Fabrication of anion complexes from 5,6-dihydrodiindolo[3,2-a:2′,3′-c]phenazine as a building block

Abstract

The easy-to-make anion receptor 5,6-dihydrodiindolo[3,2-a:2′,3′-c]phenazine (DIPZ) was employed as a versatile building block for constructing anion complexes with spherical fluoride and bromide, Y-shaped acetate and benzoate, trigonal nitrate, tetrahedral hydrogen sulfate and dihydrogen phosphate, and octahedral hexafluorosilicate anions. A systematical solid-state study was performed to investigate the influence of the size, basicity and geometry of anionic substrates on anion-binding affinities and modes, even the assembling structures in the solid state. The combination of conventional hydrogen bonding (N–H hydrogen bonding) and other weak interactions (aryl C–H aryl hydrogen bonding and π–π stacking interaction) led to the formation of a series of anion-assisted supramolecular architectures with specific aggregates, such as 5 : 6 binding structure, anionic dimer and chain, cationic channel and sandwich-like structure, which have attracted extensive interests in supramolecular chemistry.