A class of organic cages featuring twin cavities

Abstract

A variety of organic cages with different geometries have been developed during the last decade, most of them exhibiting a single cavity. In contrast, the number of organic cages featuring a pair of cavities remains scarce. These structures may pave the way towards novel porous materials with emergent properties and functions.We herein report on rational design of a three-dimensional hexaformyl precursor 1, which exhibits two types of conformers, i.e. Conformer-1 and -2, with different cleft positions and sizes. Aided by molecular dynamics simulations, we select two triamino conformation capturers (denoted CC). Small-sized CC-1 selectively capture Conformer-1 by matching its cleft size, while the large-sized CC-2 is able to match and capture both conformers. This strategy allows the formation of three compounds with twin cavities, which we coin diphane. The self-assembly of diphane units results in superstructures with tunable proton conductivity, which reaches up to 1.37×10-5 S cm-1.

A double-decker cage for allosteric encapsulation of ATP

“…1B). 18 It follows that previously studied 19 hexakis aldehyde 2 could undergo reversible imine condensations 20 with two molecules of tris amine 3 to, after a functional group transformation, give double-decker cage 1 (Fig. 1C).…”

Supramolecular Proton Conductors Self-Assembled by Organic Cages

“…Organic cages are a class of molecules with intrinsic nanosized cavity and rich structural diversity, which recently have attracted increasing attention. − By virtue of their excellent solution-processability, which are distinct from MOF and COF, they can self-assemble in solution into defect-free crystalline porous materials. Organic cages recently were applied for the preparation of solid-state proton conductors by the Cooper laboratory and our group, which hitherto had remained the only two examples for such a purpose. In this article, we would like to report on the rational design of two organic cages featuring different shapes, cavities, and number of proton carrier anchors.…”

Short hydrogen-bond network confined on COF surfaces enables ultrahigh proton conductivity

“…3b ), corresponding to the average number of confined water molecules per -SO 3 H for TpPa-SO 3 H and TpBd-SO 3 H, repectively. Accordingly, the distribution of surface water/hydronium will be constrained in a limited region, outside which the donor-acceptor water bridge is no longer valid 38 . The short group distance in TpBd-SO 3 H gives rise to the overlap between these regions and therefore an interconnected H-bond network shared with WHD, while the group distance in TpPa-SO 3 H is large enough to allow the isolation of each water domain, leading to a discrete H-bond network.…”