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Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
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Cyclization of Ynamide-Tethered 1,3,8-Triynes
Venkata R Sabbasani1, Hyunjin Lee1, Peipei Xie2
1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|April 22, 2017
Summary
A new thermal cyclization reaction efficiently creates a complex pyranopyridine skeleton from ynamide-tethered triynes. This organic synthesis breakthrough offers a novel route to valuable heterocyclic compounds.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Heterocyclic Chemistry
Background:
- Ynamide-tethered 1,3,8-triynes represent a class of compounds with potential for novel cyclization reactions.
- The synthesis of complex heterocyclic skeletons like pyranopyridines is of significant interest in medicinal and materials chemistry.
Purpose of the Study:
- To describe a facile thermal cyclization reaction for constructing the 3,5,6,7-tetrahydro-1H-pyrano[3,4-c]pyridine skeleton.
- To explore the potential reaction mechanism and identify key factors for successful cyclization.
Main Methods:
- Thermal cyclization of ynamide-tethered 1,3,8-triynes.
- Analysis of reaction products to determine the formed skeleton.
- Tentative mechanistic studies involving proposed intermediates and reaction steps.
Main Results:
- A facile thermal cyclization method was developed for ynamide-tethered 1,3,8-triynes.
- The reaction successfully yielded the 3,5,6,7-tetrahydro-1H-pyrano[3,4-c]pyridine skeleton.
- The proposed mechanism involves either a keteniminium or biradical intermediate followed by a hydride/hydrogen shift.
Conclusions:
- This study presents a novel and efficient synthetic route to pyranopyridine derivatives.
- The reaction's success is dependent on appropriate electronic activation for hydride/hydrogen transfer.
- Further mechanistic investigations are warranted to fully elucidate the reaction pathway.
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