Nanostructured Catalytic Reactors Produced by Supramolecular Materials Based on Aromatic Amphiphiles

Abstract

Enzymes are natural catalysts that are composed of highly ordered proteins and provide nanostructured active sites for specific reactions. The ability of enzymes to efficiently bind substrates in aqueous environments and spontaneously release products upon reaction completion has inspired the development of synthetic catalysts (enzyme mimetics) based on well-organized supramolecular nanomaterials. The amphiphilicity of these materials can be exploited to dissolve hydrophobic substrates in polar solvents and gather such substrates in the hydrophobic confined spaces of supramolecular cavities. The result is high local concentrations of substrates, which allows organic reactions to proceed in polar solvent environments. Supramolecular materials can also reversibly change their functions and structures in response to external stimuli such as temperature, solvents, and guest molecules to realize the on/off switching of supramolecular catalyst-promoted reactions. In this Perspective, we introduce supramolecular materials produced by the self-assembly of aromatic amphiphiles and discuss their applications as catalysts for various reactions in polar solvents. Furthermore, we highlight the potential of these materials and provide insights into the related next-generation catalysts.

Chiral Supramolecular Self-Assembly Catalysts with Enhanced Metal Ion Interaction for Higher Enantioselectivity

“…15−17 Moreover, chiral supramolecular selfassembly catalysts have the advantages of good catalytic efficiency and cyclic stability. 9,14,18 In order to achieve higher enantioselectivity, more effort has been devoted to investigating the effect of various noncovalent interactions, like hydrogen bonds, van der Waals, amphiphilic, and π−π interactions, for the building and tuning of supramolecular scaffolds themselves with chiral morphology. 19−23 However, less attention was paid to the interaction between the metal ions as catalytic centers and the supramolecular scaffolds as chiral substrates.…”

“…Catalysts with high enantioselectivity play a significant role in obtaining specific enantiomers from organic asymmetric reactions and thus have been widely used in the fabrication of chiral drugs, agricultural chemicals, and functional chiral materials. − With the fast development of supramolecular chemistry, the chiral catalysts constructed from supramolecular self-assembly have attracted increasing attention due to their easier preparation process and more flexible tunability than the chiral small molecular catalysts. − The design or modification of traditional chiral small molecular catalysts is based on the method of organic synthesis, through the modification of covalent bonds, which requires higher energy input and a more complex process. − Moreover, chiral supramolecular self-assembly catalysts have the advantages of good catalytic efficiency and cyclic stability. ,, In order to achieve higher enantioselectivity, more effort has been devoted to investigating the effect of various noncovalent interactions, like hydrogen bonds, van der Waals, amphiphilic, and π–π interactions, for the building and tuning of supramolecular scaffolds themselves with chiral morphology. − However, less attention was paid to the interaction between the metal ions as catalytic centers and the supramolecular scaffolds as chiral substrates. A strategy that can effectively reinforce such metal ion–supramolecular scaffold interaction may potentially intensify the chirality transfer from the supramolecular scaffold to the metal ion and finally to the reactant molecule, achieving the enhanced catalytic enantioselectivity.…”

Assembly-Driven Oxidative Degradation of Melarsomine Triggered by Cyanuric Acid

“…Supramolecular chemistry explores the unique noncovalent interactions between molecules, such as hydrogen bonds, hydrophobic interactions, van der Waals forces, π–π interactions, and ionic bonds. − Specific structures, including micelles, vesicles, sheets, networks, and ribbons, can be formed through the precise control of noncovalent interactions. − Combining multiple molecules results in supramolecules with novel and distinct functions not observed in individual molecules. , Among these functions, assembly-driven reactions involve initiating or controlling a particular chemical reaction by forming a supramolecule . This approach enables the simple and efficient control of reactions without modification of other variables.…”

“… 9 , 10 Among these functions, assembly-driven reactions involve initiating or controlling a particular chemical reaction by forming a supramolecule. 11 This approach enables the simple and efficient control of reactions without modification of other variables. For example, Jiang et al assembled a monomer containing an azide and an alkyne into a nanofiber to induce a click reaction without using a metal catalyst.…”

Transformation of Supramolecular Membranes to Vesicles Driven by Spontaneous Gradual Deprotonation on Membrane Surfaces

“…Although the transformation between membranes and vesicles is a significant phenomenon, the lack of a detailed understanding of the transformation at the molecular level can limit the development of synthetic systems to mimic the natural and reversible dynamic system. Therefore, investigations via synthetic model systems in the detailed mechanisms of such sophisticated membrane transformations can provide a tool for emerging synthetic materials, such as those required for drug delivery systems, , biosensors, − and catalysts. − …”