In this frontier article we highlight recent advances in subcomponent self-sorting in self-assembled metal–ligand cage complexes, with a focus on selective discrimination between ligands that contain highly similar metal-coordinating groups. Effects such as varying ligand length, coordination angle and backbone flexibility, as well as the introduction of secondary weak forces such as hydrogen bonds can be exploited to favor either narcissistic or social self-sorting. We highlight these creative solutions, and emphasize the challenges that remain in the development of functional self-assembled heterocomplexes.
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No, Not That Way, the Other Way: Creating Active Sites in Self-Assembled Host Molecules
This Account describes our efforts over the last decade to synthesize self-assembled metal–ligand cage complexes that display reactive functional groups on their interiors. This journey has taken us down a variety of research avenues, including studying the mechanism of reversible self-assembly, analyzing ligand self-sorting properties, post-assembly reactivity, molecular recognition, and binding studies, and finally reactivity and catalysis. Each of these individual topics are discussed here, as are the lessons learned along the way and the future research outlook. These self-assembled hosts are the closest mimics of enzymes to date, as they are capable of size- and shape-selective molecular recognition, substrate activation and turnover, as well as showing less common ‘biomimetic’ properties such as the ability to employ cofactors in reactivity, and alter the prevailing mechanism of the catalyzed reactions. 1 Introduction 2 Paddlewheels and Self-Sorting Behavior 3 First-Row Transition-Metal-Mediated Assembly: Sorting and Stereochemical Control 4 Post-Assembly Reactivity 5 Molecular Recognition and Catalysis 6 Conclusions and Outlook
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- Award ID(s):
- 1708019
- NSF-PAR ID:
- 10185188
- Date Published:
- Journal Name:
- Synlett
- ISSN:
- 0936-5214
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract We report the synthesis of a novel metal–organic capsule constructed from six pyrogallol[4]arene macrocycles, which are switched together by 16 FeIIIand 16 CoIIions. This supramolecular structure is the first instance of a spheroidal heterometallic nanocage assembled through a one‐step metal–ligand coordination approach. This new assembly also demonstrates an important proof of concept through the formation of multiple heterometallic metal–metal interactions within the capsule framework. Photophysical and electrochemical studies of self‐assembled capsule films indicate their potential as semiconductors. These materials display unexpected photoelectric conversion properties, thus representing an emergent phenomenon in discrete metal–organic supramolecular assemblies.
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1055/s-0040-1707125
