Cubane-forming cyclic dienes that exhibit orthogonal reactivities in the solid state
Changan Li1, Michael A Sinnwell1, Dale C Swenson1
1Department of Chemistry, University of Iowa, Iowa City, IA 52242-1294, USA. len-macgillivray@uiowa.edu.
Chemical Communications (Cambridge, England)
|June 14, 2021
Summary
Photoirradiation of a binary cocrystal yields a highly-symmetric tetraacid cage via double [2+2] photodimerization. A second diene forms a tetramethyl cubane-like cage, demonstrating regioselective synthesis.
Area of Science:
- Organic Chemistry
- Photochemistry
- Supramolecular Chemistry
Background:
- Cocrystals offer unique reactivity pathways not observed in individual components.
- Photodimerization is a key reaction in organic synthesis for forming cyclic structures.
- Understanding regioselectivity in cocrystal reactions is crucial for targeted synthesis.
Purpose of the Study:
- To investigate the photochemical behavior of a binary cocrystal of two distinct cyclic dienes.
- To explore the formation of complex cage structures through photodimerization within a cocrystal.
- To achieve regioselective and quantitative synthesis of novel cage compounds.
Main Methods:
- Formation of a binary cocrystal from two different cyclic dienes.
- Photoirradiation of the cocrystal under specific conditions.
- Analysis of the resulting products using structural authentication methods.
Main Results:
- Regioselective and quantitative formation of a highly-symmetric cubane-like tetraacid cage.
- The tetraacid cage is generated through a double [2+2] photodimerization of one diene component.
- The second, photostable diene in the cocrystal undergoes a separate double [2+2] photodimerization to form a tetramethyl cubane-like cage.
Conclusions:
- Binary cocrystals can direct the regioselective photodimerization of their components.
- This method provides a quantitative route to complex, highly-symmetric cage molecules.
- The stereochemistry of the synthesized cages is confirmed, validating the reaction pathway.
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