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This study explores the dynamic self-assembly and disassembly of hypervalent iodine-based macrocycles (HIMs) guided by secondary bonding interactions. The reversible disassembly and reassembly of HIMs are facilitated through anion binding via the addition of tetrabutylammonium (TBA) salts or removal of the anion by the addition of silver nitrate. The association constants for HIM monomers with TBA(Cl) and TBA(Br) are calculated and show a correlation with the strength of the iodine–anion bond. A unique tetracoordinate hypervalent iodine-based compound was identified as the disassembled monomer. Last, the study reveals the dynamic bonding nature of these macrocycles in solution, allowing for rearrangement and participation in dynamic bonding chemistry.
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This content will become publicly available on January 3, 2026
Pi-extended hypervalent iodine macrocycles and their supramolecular assembly with Buckminsterfullerene
A series of valine functionalized supramolecular hypervalent iodine macrocycles (HIMs) with enlarged aromatic cores, including naphthalene and anthraquinone, have been synthesized. Single crystal analysis shows the macrocycles consist of a slightly distorted cyclic planner interior with three carbonyl oxygens from the amino acid residues facing towards the center of the macrocycle and all three alkyl groups above one plane. Owing to the enlarged aromatic core, the naphthalene-based HIMs were successfully co-crystallized with Buckminsterfullerene (C60) into a long-range columnar supramolecular structure. The assembled architecture displays a long-range pattern between HIM and C60 in a 2 : 3 ratio, respectively. Disassembly of the HIMs can be accomplished by adding anions of tetrabutylammonium (TBA) salts that selectively bind with the electron deficient iodine center in HIM systems. A comparative study of the associations constants and the binding energies for different aromatic-based HIMs with TBA(Cl) and TBA(Br) is presented.
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- Award ID(s):
- 2003654
- PAR ID:
- 10566294
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 13
- Issue:
- 2
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 842-848
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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