Helically Chiral 1-Sulfur-Functionalized [6]Helicene: Synthesis, Optical Resolution, and Functionalization
Tetsuya Tsujihara1, Da-Yang Zhou2, Takeyuki Suzuki2
1Department of Medicinal and Organic Chemistry, School of Pharmacy, Iwate Medical University , Yahaba, Iwate 028-3694, Japan.
Organic Letters
|June 8, 2017
Summary
Researchers synthesized and resolved a helically chiral thiol, creating enantiopure sulfur-functionalized [6]helicenes. A new enantiopure [7]thiahelicene with a thiophene ring was also successfully synthesized.
Area of Science:
- Organic Chemistry
- Stereochemistry
- Materials Science
Background:
- Helicenes are polycyclic aromatic hydrocarbons characterized by axial chirality.
- Sulfur-functionalized helicenes offer unique electronic and optical properties.
- Enantioselective synthesis of complex chiral molecules remains a significant challenge in chemistry.
Purpose of the Study:
- To report the synthesis and optical resolution of helically chiral 5,6,9,10-tetrahydro-1-[6]helicenethiol.
- To achieve enantiopure 1-sulfur-functionalized [6]helicenes through subsequent transformations.
- To synthesize a novel enantiopure [7]thiahelicene incorporating a thiophene moiety.
Main Methods:
- Asymmetric synthesis and chiral chromatography for optical resolution.
- Functionalization of the thiol group to introduce sulfur.
- Multi-step synthesis to construct the [7]thiahelicene skeleton.
Main Results:
- Successful synthesis and optical resolution of the target helicenethiol.
- Generation of enantiopure sulfur-functionalized [6]helicenes.
- Characterization of a novel enantiopure [7]thiahelicene with a terminal thiophene ring.
Conclusions:
- The study demonstrates a viable route to enantiopure sulfur-containing helicenes.
- The developed methods allow for the creation of complex chiral sulfur-heterocyclic systems.
- The synthesized [7]thiahelicene represents a new class of chiral materials with potential applications.
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