Cycloglycolurils: Hybrid Glycoluril-Cyclobenzil Macrocycles
Ashokkumar Basavarajappa1, Xiqu Wang1, Ognjen Š Miljanić1,2
1Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States.
Organic Letters
|April 16, 2024
Summary
Researchers synthesized novel glycoluril macrocycles using solvent-free methods. These new macrocycles feature unique structures and potential for guest binding due to N-H motifs.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Crystal Engineering
Background:
- Macrocyclic compounds are crucial in supramolecular chemistry for host-guest interactions.
- Glycoluril-based macrocycles offer unique structural and binding properties.
- Developing new synthetic routes for complex macrocycles is an ongoing challenge.
Purpose of the Study:
- To synthesize novel glycoluril macrocycles from readily available precursors.
- To investigate the structural characteristics and supramolecular assembly of these new macrocycles.
- To explore the potential of these macrocycles in guest binding applications.
Main Methods:
- Solvent-free condensation reactions between cyclotetrabenzil/cyclotribenzoin precursors and urea.
- Single-crystal X-ray diffraction to determine the molecular and crystal structures.
- Analysis of structural features related to supramolecular packing and potential host-guest interactions.
Main Results:
- Successful synthesis of two novel glycoluril macrocycles.
- The cyclotetra(p-phenylene)glycoluril macrocycle adopted a twisted ring conformation.
- The cyclotri(m-phenylene)glycoluril hybrid displayed a tubular supramolecular packing.
- Identification of available N-H motifs within the macrocycle structures.
Conclusions:
- A new class of glycoluril macrocycles has been established.
- The synthesized macrocycles exhibit distinct structural features and supramolecular arrangements.
- These macrocycles hold promise for applications in host-guest chemistry due to their functional N-H groups.
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