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Synthesis 2019; 51(22): 4263-4270
DOI: 10.1055/s-0039-1690680
DOI: 10.1055/s-0039-1690680
paper
Metal-Free Hydroamination of Alkynes: A Mild and Concise Synthesis of Thiazolo[3,2-a]indoles and their Cytotoxic Activity
The authors gratefully acknowledge the financial support provided by the Natural Sciences and Engineering Research Council of Canada (NSERC), Nipissing University, the Canada Foundation for Innovation (CFI) and the Northern Ontario Heritage Fund Corporation (NOHFC) to conduct this research.Further Information
Publication History
Received: 08 July 2019
Accepted after revision: 29 August 2019
Publication Date:
24 September 2019 (online)

Abstract
A metal-free, mild and efficient method for the synthesis of thiazolo[3,2-a]indoles has been developed starting from indoline-2-thiones. The reaction methodology involves first the formation of thermally labile 2-(prop-2-ynylthio)-1H-indole intermediates, which undergo base-mediated intramolecular hydroamination to produce the title compounds in excellent yields.
Key words
indole-fused heterocycles - thiazolo[3,2-a]indoles - metal-free hydroamination - indoline-2-thiones - intramolecular cyclizationSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0039-1690680.
- Supporting Information
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