Cargando…
Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals
Herein, we report a facile visible light induced copper catalyzed controlled oxidation of terminal C[triple bond, length as m-dash]C alkynes to α-keto esters and quinoxalines via formation of phenylglyoxals as stable intermediates, under mild conditions by using molecular O(2) as a sustainable oxida...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Royal Society of Chemistry
2018
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6167948/ https://www.ncbi.nlm.nih.gov/pubmed/30294421 http://dx.doi.org/10.1039/c8sc03447h |
_version_ | 1783360290695413760 |
---|---|
author | Das, Deb Kumar Kumar Pampana, V. Kishore Hwang, Kuo Chu |
author_facet | Das, Deb Kumar Kumar Pampana, V. Kishore Hwang, Kuo Chu |
author_sort | Das, Deb Kumar |
collection | PubMed |
description | Herein, we report a facile visible light induced copper catalyzed controlled oxidation of terminal C[triple bond, length as m-dash]C alkynes to α-keto esters and quinoxalines via formation of phenylglyoxals as stable intermediates, under mild conditions by using molecular O(2) as a sustainable oxidant. The current copper catalysed photoredox method is simple, highly functional group compatible with a broad range of electron rich and electron poor aromatic alkynes as well as aliphatic alcohols (1°, 2° and 3° alcohols), providing an efficient route for the preparation of α-keto esters (43 examples), quinoxaline and naphthoquinone with higher yields than those in the literature reported thermal processes. Furthermore, the synthetic utility of the products has been demonstrated in the synthesis of two biologically active molecules, an E. coli DHPS inhibitor and CFTR activator, using the current photoredox process. In addition, we applied this methodology to the one-pot synthesis of a heterocyclic compound (quinoxaline, an FLT3 inhibitor) by trapping the intermediate phenylglyoxal with O-phenylenediamine. The intermediate phenylglyoxal can also be isolated and further reacted with an internal alkyne to form naphthoquinone. This process can be readily scaled up to the gram scale. |
format | Online Article Text |
id | pubmed-6167948 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | Royal Society of Chemistry |
record_format | MEDLINE/PubMed |
spelling | pubmed-61679482018-10-05 Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals Das, Deb Kumar Kumar Pampana, V. Kishore Hwang, Kuo Chu Chem Sci Chemistry Herein, we report a facile visible light induced copper catalyzed controlled oxidation of terminal C[triple bond, length as m-dash]C alkynes to α-keto esters and quinoxalines via formation of phenylglyoxals as stable intermediates, under mild conditions by using molecular O(2) as a sustainable oxidant. The current copper catalysed photoredox method is simple, highly functional group compatible with a broad range of electron rich and electron poor aromatic alkynes as well as aliphatic alcohols (1°, 2° and 3° alcohols), providing an efficient route for the preparation of α-keto esters (43 examples), quinoxaline and naphthoquinone with higher yields than those in the literature reported thermal processes. Furthermore, the synthetic utility of the products has been demonstrated in the synthesis of two biologically active molecules, an E. coli DHPS inhibitor and CFTR activator, using the current photoredox process. In addition, we applied this methodology to the one-pot synthesis of a heterocyclic compound (quinoxaline, an FLT3 inhibitor) by trapping the intermediate phenylglyoxal with O-phenylenediamine. The intermediate phenylglyoxal can also be isolated and further reacted with an internal alkyne to form naphthoquinone. This process can be readily scaled up to the gram scale. Royal Society of Chemistry 2018-08-29 /pmc/articles/PMC6167948/ /pubmed/30294421 http://dx.doi.org/10.1039/c8sc03447h Text en This journal is © The Royal Society of Chemistry 2018 https://creativecommons.org/licenses/by/3.0/This article is freely available. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence (CC BY 3.0) |
spellingShingle | Chemistry Das, Deb Kumar Kumar Pampana, V. Kishore Hwang, Kuo Chu Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals |
title | Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals
|
title_full | Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals
|
title_fullStr | Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals
|
title_full_unstemmed | Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals
|
title_short | Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals
|
title_sort | copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals |
topic | Chemistry |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6167948/ https://www.ncbi.nlm.nih.gov/pubmed/30294421 http://dx.doi.org/10.1039/c8sc03447h |
work_keys_str_mv | AT dasdebkumar coppercatalyzedphotoredoxsynthesisofaketoestersquinoxalineandnaphthoquinonecontrolledoxidationofterminalalkynestoglyoxals AT kumarpampanavkishore coppercatalyzedphotoredoxsynthesisofaketoestersquinoxalineandnaphthoquinonecontrolledoxidationofterminalalkynestoglyoxals AT hwangkuochu coppercatalyzedphotoredoxsynthesisofaketoestersquinoxalineandnaphthoquinonecontrolledoxidationofterminalalkynestoglyoxals |