Hexameric C-alkylpyrogallol[4]arene molecular capsules sustained by metal-ion coordination and hydrogen bonds

Abstract

Large multicomponent nanospheroid arrays consisting of six C-pentylpyrogallol[4]arene molecules and 12 Ga3+ metal-ions which in turn enclose 1150 A3 of chemical space are reported.

Metallo-supramolecular capsules

“…From the work reviewed in this article, we have also shown that they are also useful templates for metal-organic analogues [116,[118][119][120][121]124,127]. The remarkable replacement of 48 hydrogen atoms in the hydrogen-bonded 'seam' with 24 copper Fig.…”

“…When considering some of the largest supramolecular container assemblies formed to date [16,19,23,[47][48][49][50][68][69][70][84][85][86], hydrogen-bonded pyrogallol- [4]arene capsules (either dimeric or hexameric) are useful for the encapsulation of reasonably large non-solvent molecules, as identified by X-ray diffraction studies [96][97][98][99][100][101][102][103]116,[118][119][120]. From the work reviewed in this article, we have also shown that they are also useful templates for metal-organic analogues [116,[118][119][120][121]124,127].…”

“…When an acetonitrile/water solvent system is used instead of acetone/water, crystals can be grown for a number of mixtures containing gallium and various C-alkylpyrogallol [4]arenes [120]. In some cases we have found these to be unstable toward solvent loss after removal from the mother liquor.…”

“…The interior of the assembly was found to contain acetone and waters of crystallisation, the latter of which form zig-zag chains that span the width of the assembly. Within this system, PgC 3 can be exchanged for PgC 5 , and single crystals suitable for X-ray diffraction studies can be grown [120]. Structural analysis of these crystals shows the same gallium nano-capsule motif, albeit with the different chain lengths radiating from the 'lower rims' of the pyrogallol [4]arenes.…”

A Ga3+self-assembled fluorescent probe for ATP imaging in vivo

“…The turn-on fluorescence signal can effectively discriminate ATP from ADP and adenosine 5′-monophosphate (AMP). Ga 3 þ ions were found to easily coordinate with oxygen atoms of hydroxyphenyl segments (Hastings et al, 2014;McKinlay et al, 2005McKinlay et al, , 2006. DHBO ligand is a typical fluorophore known for its excited state intramolecular proton transfer (ESIPT) characteristic (Xu et al, 2014).…”