Oxidative Approach Enables Efficient Access to Cyclic Azobenzenes.
Martin S Maier1,2, Katharina Hüll1,2, Martin Reynders1,2
1Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany.
Journal of the American Chemical Society
|October 5, 2019
Summary
Cyclic diazocines, versatile photoswitches, are now synthetically accessible. A new oxidative cyclization method enables rapid, gram-scale synthesis of functionalized diazocines for diverse applications.
Area of Science:
- Organic Chemistry
- Photochemistry
- Materials Science
Background:
- Azobenzenes are crucial photoswitches utilized across photopharmacology and material sciences.
- Cyclic diazocines, a newer class, possess unique properties but face synthetic limitations.
Purpose of the Study:
- To develop a general, high-yielding synthetic protocol for accessing diversely functionalized cyclic diazocines.
- To explore the impact of substituents on the photoisomerization and thermal relaxation of diazocines.
Main Methods:
- Oxidative cyclization of dianilines.
- Modular substrate synthesis for diverse functionalization.
- Gram-scale synthesis of cyclic diazocines.
Main Results:
- A robust protocol for synthesizing functionalized cyclic diazocines was established.
- Substituent effects on photoisomerization and thermal relaxation were systematically investigated.
- The method facilitated the synthesis of a novel nine-membered cyclic azobenzene.
Conclusions:
- The developed method significantly enhances the synthetic accessibility of cyclic diazocines.
- This work paves the way for incorporating diazocines into various functional molecules.
- The findings unlock the potential of diazocines as advanced photoswitchable materials.
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