Synthesis of a Highly Electron-Deficient, Water-Stable, Large Ionic Box: Multielectron Accumulation and Proton Conductivity

Abstract

π-acidic boxes exhibiting electron reservoir and proton conduction are unprecedented because of their instability in water. We present the synthesis of one of the strongest electron-deficient ionic boxes showing e − uptake as well as proton conductivity. Two large anions fit in the box to form anion−π interactions and form infinite anion−solvent wires. The box with NO 3 − •••water wires confers high proton conductivity and presents the first example that manifests redox and ionic functionality in an organic electron-deficient macrocycle.

Anion‐π Interaction for Molecular Recognition of Anions: Focus on Cooperativity with Hydrogen Bonding

“…[161] This cage offers a huge cavity of ~7.6 Å (Reprinted with permission from [105] . Copyright (2019), American Chemical Society) (Reprinted with permission from [160] . Copyright (2022), American Chemical Society).…”

“…Copyright (2022), American Chemical Society). Another example was proposed by Mukhopadhyay et al [160] In this structure 137, two imidazolium groups are grafted next to the NDI electron-deficient group, amplifying the electron deficiency of the NDI. This results into stable complexes with multiple anions trapped within the cavity (2 hexafluorophosphate and up to 4 nitrate anions).…”

“…Another example was proposed by Mukhopadhyay et al [160] . In this structure 137 , two imidazolium groups are grafted next to the NDI electron‐deficient group, amplifying the electron deficiency of the NDI.…”

Synthesis and Properties of Electron‐Deficient and Electron‐Rich Redox‐Active Ionic π‐Systems

“…Recently, our group reported a new supramolecular host that can accumulate electrons at low potentials and transport ions leading to high proton conductivity. [12] Such organic mixed ionic-electronic conductors have found applications in batteries, supercapacitors, actuators, ion-pumps, neuromorphic computing, etc. [13][14][15][16][17] In this review article, we make an effort to provide an account on the synthesis and properties of organic ionic systems, which are electroactive in nature.…”

“…Also, important will be designed systems that combine efficient ion transport and electron accumulation as well as its transport. Recently, our group reported a new supramolecular host that can accumulate electrons at low potentials and transport ions leading to high proton conductivity [12] . Such organic mixed ionic‐electronic conductors have found applications in batteries, supercapacitors, actuators, ion‐pumps, neuromorphic computing, etc [13–17] .…”