How to Make Weak Noncovalent Interactions Stronger

Abstract

By employing noncovalent interactions, chemists have constructed a variety of molecular aggregates with well-defined structures and fascinating properties. In fabricating stable and large molecular assemblies, noncovalent interactions with high binding strength are needed. This Concept summarizes some strategies to modify and optimize the structures of building blocks for making weak noncovalent interactions stronger. The strategies include: 1) Preorganization of binding sites; 2) spatial confinement effects; 3) multivalent enhancement; 4) synergistic binding with multiple forces. Examples of the fabrication of supramolecular architectures by utilizing these strategies are presented and discussed. Guidance is offered in the construction and fabrication of stable molecular assemblies and supramolecular materials.

Highly Ordered Self‐Assembly of Native Proteins into 1D, 2D, and 3D Structures Modulated by the Tether Length of Assembly‐Inducing Ligands

“…In the field of supramolecular chemistry,ithas been known that relatively rigid linkers do promote the elongation of supramolecular polymers. [23] Considering the possible supramolecular polymeric structure of LecA/R2G,i tc an be predicted that the rigid diagonal-diagonal linkages result in larger assemblies.While for R4G/R5G,inaddition to the short-short and diagonal-diagonal linkages,t he long-long linkage was also observed (Figure S17 and S18). However,t he possible assemblies of LecA/R4G or LecA/R5G based on the longlong or short-short linkages were soft compared to those formed in the diagonal-diagonal linkages (Figure S16 b,c).…”

“…Tw oLecA/R2G complexes were first placed close to each other through long-long linkages.H owever,e ven if they were pushed close,astable structure could not be formed (Supporting Information, Figure S13 a), since the p-p stacking between the neighboring RhBs did not take place,which was very similar to the result of LecA/R1G.H owever,w hen two LecA/R2Gsw ere placed close to each other in the short-short and diagonal-diagonal linkages,t he p-p stacking between small molecules on the different LecAs was quickly formed ( Figure S13 ba nd Figure 3i). [23] Considering the possible supramolecular polymeric structure of LecA/R2G,i tc an be predicted that the rigid diagonal-diagonal linkages result in larger assemblies.While for R4G/R5G,inaddition to the short-short and diagonal-diagonal linkages,t he long-long linkage was also observed ( Figure S17 and S18). In the field of supramolecular chemistry,ithas been known that relatively rigid linkers do promote the elongation of supramolecular polymers.…”

Supramolecular Guest–Host Interactions for the Preparation of Biomedical Materials

“…[66][67] For further information regarding polymer architecture and molecular organization in guest-host hydrogels and their influence on bulk hydrogel properties, the reader is referred to extensive reviews that cover these topics. 2,68 Beyond the ability to assemble into networks, supramolecular guest-host interactions may be used to introduce structure at the nano-and micro-scales. Indeed, the organization of many natural structures is driven by supramolecular interactions, such as native extracellular matrix (e.g., fibrillar structure of collagen) and the DNA superstructure.…”

Molecular Tweezer/Guest Complexation with the Participation of Hydrogen Bonds: Toward the Formation of Orthogonal Supramolecular Polymers

“…In detail, fitting the exothermic isotherm data with the two‐sites model provides the K a,1 value of 6.63×10 5 M −1 and K a,2 value of 1.53×10 4 M −1 (Figure c). As widely known, K a,2 / K a,1 ratio vale should be around 0.25 for the statistical complexation . Herein, the decreased K a,2 /K a,1 value suggests the involvement of anti‐cooperative complexation events for the divalent molecular tweezer/guest complexation process.…”