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Synlett 2017; 28(16): 2189-2193
DOI: 10.1055/s-0036-1588461
DOI: 10.1055/s-0036-1588461
letter
Heat Versus Basic Conditions: Intramolecular Dehydro-Diels–Alder Reaction of 1-Indolyl-1,6-heptadiynes for the Selective Synthesis of Substituted Carbazoles
This project was supported in part by JSPS KAKENHI (26410120)Further Information
Publication History
Received: 01 May 2017
Accepted after revision: 19 May 2017
Publication Date:
06 July 2017 (online)
![](https://www.thieme-connect.de/media/synlett/201716/lookinside/thumbnails/st-2017-u0315-l_10-1055_s-0036-1588461-1.jpg)
Abstract
The intramolecular dehydro-Diels–Alder reaction of 1-indolyl-1,6-heptadiynes proceeds smoothly under rather mild heating conditions to give substituted carbazoles in moderate to good yields. The reaction of 7-aryl-1-indolyl-1,6-heptadiynes under heating gives the corresponding carbazoles chemoselectively in high yields, whereas the reaction under basic conditions gives naphthalenes as major products.
Key words
carbazoles - indoles - naphthalenes - dehydro-Diels–Alder reaction - intramolecular Diels–Alder reaction - chemoselectivitySupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0036-1588461.
- Supporting Information
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