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Published on: February 7, 2019
Enantiomerically pure alleno-acetylenic macrocycles: synthesis, solid-state structures, chiroptical properties, and
Pablo Rivera-Fuentes1, José Lorenzo Alonso-Gómez, Ana G Petrovic
1Laboratorium für Organische Chemie, ETH Zürich, Hönggerberg, HCI, 8093 Zürich, Switzerland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 4, 2010
Summary
New chiral alleno-acetylenic macrocycles were synthesized and characterized. Their unique electronic properties and stability were explained by relating molecular orbital topology to structural features, revealing them as rare anti-aromatic Hückel compounds.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Computational Chemistry
Background:
- Alleno-acetylenic macrocycles represent a unique class of organic compounds.
- Understanding their stereochemistry and electronic properties is crucial for developing novel materials.
- Chiral separation and characterization techniques are essential for studying enantiomerically pure compounds.
Purpose of the Study:
- To synthesize novel enantiomerically pure alleno-acetylenic macrocycles.
- To characterize their stereoisomers and elucidate their chiroptical properties.
- To investigate the electronic structure and stability of these macrocycles using computational methods.
Main Methods:
- Oxidative homocoupling of optically active 1,3-diethynylallenes.
- Chiral High-Performance Liquid Chromatography (HPLC) for enantiomer separation.
- X-ray crystallography for structural determination.
- Quantum chemical calculations (CAM-B3LYP) for chiroptical properties and electronic structure analysis.
Main Results:
- Successful synthesis of enantiomerically pure alleno-acetylenic macrocycles.
- Isolation and characterization of both chiral and achiral stereoisomers.
- Determination of the X-ray structures for D(4)- and C(2)-symmetric macrocycles.
- Explanation of intense chiroptical response through molecular orbital topology and electronic properties.
- Identification of these macrocycles as stable, formally anti-aromatic Hückel compounds.
Conclusions:
- Enantiomerically pure alleno-acetylenic macrocycles can be effectively synthesized and separated.
- Their unique chiroptical properties are directly linked to their molecular structure and electronic configuration.
- These compounds represent a rare class of stable, anti-aromatic Hückel systems with potential for further research and applications.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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