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Abstract Thiol‐disulfide interchange has been a large field of study for both biochemists and physical organic chemists alike due to its prevalence within biological systems and fundamentally interesting dynamic nature. More recently, efforts have been made to harness the power of this reversible reaction to make self‐assembling systems of macrocyclic molecules. However, less effort has focused on the fundamental work of isolating these assemblies and studying the factors that control the assembly and sorting of these emerging cyclic systems. A more complete fundamental understanding of factors controlling such self‐assembly could also improve understanding of the complex systems biology of thiol exchange while also aiding in the design of dynamic thiol assembly to enable applications ranging from drug delivery and biosensing to new materials synthesis. We have shown previously that pnictogen‐assisted self‐assembly enables formation of discrete disulfide macrocycles and cages without competition from polymer formation for a wide variety of alkyl thiols. In this study, we report the expansion of pnictogen‐assisted self‐assembly methods to form disulfide bearing macrocycles from aryl thiol containing ligands, allowing access to previously unreported molecules. These studies complement classical physical organic and chemical biology studies on the rates and products of aryl thiol oxidation to disulfides, and we show that this self‐assembly method revises some prevailing wisdom from these key classical studies by providing new product distributions and new isolable products in cyclic disulfide formation.
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Expanding Pnictogen-Assisted Self-Assembly of Disulfide Macrocycles to Include Heteroarenes
New routes to the formation of macrocyclic molecules are of high interest to the supramolecular chemistry community and the chemistry community at large. Here we describe the incorporation of heterocyclic core units into discrete macrocycles via the utilization of a pnictogen-assisted self-assembly technique. This method allows for the rapid and efficient formation of discreet macrocyclic units from simple dithiol precursors in high yields with good control over macrocycle size. Up to this point, this technique has been reported on primarily benzylic thiol systems with very little incorporation of endohedral heteroatoms in the resulting assemblies. This study demonstrates the effective incorporation of heterocyclic core molecules allowing for the formation of a more functional cavity, resulting in the formation and crystallization of novel furan- and thiophene-based disulfide dimer and trimer macrocycles, respectively, that are isolated from a range of other larger discrete macrocycles that assemble as well. These disulfide macrocycles can be trapped as their more kinetically stable thioether congeners upon sulfur extrusion.
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- Award ID(s):
- 2003928
- PAR ID:
- 10479865
- Publisher / Repository:
- World Scientific
- Date Published:
- Journal Name:
- Journal of Porphyrins and Phthalocyanines
- Volume:
- 27
- Issue:
- 07n10
- ISSN:
- 1088-4246
- Page Range / eLocation ID:
- 1394 to 1397
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1142/S1088424623500992
