Constructing Ultrastable Metallo-Cages via In Situ Deprotonation/Oxidation of Dynamic Supramolecular Assemblies

Abstract

Coordination-driven self-assembly enables the spontaneous construction of metallo-supramolecules with high precision, facilitated by dynamic and reversible metal–ligand interactions. The dynamic nature of coordination, however, results in structural lability in many metallo-supramolecular assembly systems. Consequently, it remains a formidable challenge to achieve self-assembly reversibility and structural stability simultaneously in metallo-supramolecular systems. To tackle this issue, herein, we incorporate an acid-/base-responsive tridentate ligand into multitopic building blocks to precisely construct a series of metallo-supramolecular cages through coordination-driven self-assembly. These dynamic cagelike assemblies can be transformed to their static states through mild in situ deprotonation/oxidation, leading to ultrastable skeletons that can withstand high temperatures, metal ion chelators, and strong acid/base conditions. This in situ transformation provides a reliable and powerful approach to manipulate the kinetic features and stability of metallo-supramolecules and allows for modulation of encapsulation and release behaviors of metallo-cages when utilizing nanoscale quantum dots (QDs) as guest molecules.

Synthesis of a Triangle-Fused Six-Pointed Star and Its Electrocatalytic CO2 Reduction Activity

“…Furthermore, gradient tandem mass spectrometry (gMS 2 ) measurements show that T1 (Figures b and S138c) exhibits a superior stability at a higher collision energy range compared to R1 (Figures a and S138b), suggesting the enhanced stability of T1 . The result further strengthens the assertion that increasing the connector density contributes to improving the skeleton stability …”

“…The result further strengthens the assertion that increasing the connector density contributes to improving the skeleton stability. 82 Chronoamperometry measurements at −0.4 V vs RHE were performed in order to explore the relationship between the connector density and the catalytic stability. As shown in Figure 7e, R1/KB exhibits a stability up to 87 h (Figures 7c and S139b), with ΔFE (CO) < 0.5% consistently, while T1/KB exhibits a catalytic stability of at least 126 h (Figures 7d and S139c) under the same potential for the CO 2 RR, which is an excellent performance compared to other reported molecular catalysts (Table S10).…”

Heterometallic cages: synthesis and applications

“…Therefore, to enhance these types of applications there is a need to develop more kinetically robust MSAs. 195–198 The majority of heterometallic MSAs developed to date feature both inert and liable metal ions. Thus, it would be expected that those systems would be more robust than the related homometallic systems.…”

Metal-ion-determined geometrical configurations of metallo-cages with different emission properties

“…17,18 Inspired by the functional complexity of biomolecular systems, different metal ions have been introduced into the metallo-cages with aim to prepare highly advanced structures as well as fulfil specific applications. [19][20][21][22] It is commonly known that the structure of metallo-cages is controlled mainly by the ligands, 23 anions, 24,25 metal ions, 26 and self-assembly conditions such as concentration and temperature. 27 Apart from the ligand design, the selection of the metal ions is also crucial for the formation of supramolecular cages.…”

“…17,18 Inspired by the functional complexity of biomolecular systems, different metal ions have been introduced into the metallo-cages with aim to prepare highly advanced structures as well as fulfil specific applications. 19–22…”