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Linker-Directed Assembly of Twisted ortho-Phenylene-Based Macrocycles
Zacharias J Kinney1, C Scott Hartley1
1Department of Chemistry & Biochemistry , Miami University , Oxford , Ohio 45056 , United States.
Organic Letters
|May 16, 2018
Summary
Researchers created new macrocycles using o-phenylene tetramers and linkers. Varying linker length and connectivity yielded [1 + 1] and [2 + 2] macrocycles, influencing geometry and stability.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Materials Science
Background:
- Macrocycles are cyclic molecules with diverse applications.
- Imine condensation is a common method for synthesizing macrocycles.
- Previous work reported [3 + 3] macrocycles, but [1 + 1] and [2 + 2] were less explored.
Purpose of the Study:
- To synthesize novel [1 + 1] and [2 + 2] macrocycles using o-phenylene tetramers.
- To investigate the effect of linker connectivity and length on macrocycle formation and properties.
- To explore the stereochemical outcomes, including chirality, in the synthesized macrocycles.
Main Methods:
- Coassembly of o-phenylene tetramers with various linkers.
- Utilizing imine condensation reactions for macrocycle formation.
- Characterization of macrocycle structures and properties through analytical techniques.
Main Results:
- Successfully obtained [1 + 1] and [2 + 2] macrocycles, complementing existing [3 + 3] systems.
- Demonstrated that linker length significantly impacts o-phenylene geometry and macrocycle stability in [1 + 1] systems.
- Observed both homo- and heterochiral configurations in [2 + 2] macrocycles, indicating limited helix handedness communication.
Conclusions:
- The study expands the library of accessible macrocycles through controlled synthesis.
- Linker engineering provides a versatile strategy for tuning macrocycle properties.
- The observed chirality in [2 + 2] macrocycles opens avenues for chiral supramolecular materials.
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