Synlett 2021; 32(07): 733-737
DOI: 10.1055/a-1294-0158
letter

Late-Stage Alkylation of N-Containing Heteroarenes Enabled by Homolysis of Alkyl-1,4-dihydropyridines under Blue LED Irradiation

Xiaoping Chen
a   Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province and College of Physics and Optoelectronic Engineering Shenzhen University, Shenzhen 518060, P. R. of China
,
Xiaosheng Luo
b   Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. of China
,
Kaiqian Wang
c   College of Chemistry & Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, P. R. of China
,
Feng Liang
c   College of Chemistry & Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, P. R. of China
,
Ping Wang
b   Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. of China
› Author Affiliations
Financial support for this work was provided by the China Postdoctoral Science Foundation (2017M622747).


Abstract

Alkylated heteroarenes are widely found in bioactive molecules and pharmaceuticals. Therefore, there is great interest in developing a chemoselective alkylation of heteroarenes under mild conditions, particularly during a late-stage functionalization step for the purpose of rapid derivatization. Herein, we introduce an efficient visible-light-promoted C–H alkylation of nitrogen-containing heteroarenes by using C4-alkyl 1,4-dihydropyridines (DHPs) as radical precursors at ambient temperatures. A broad scope of heteroarenes, such as 4-hydroxyquinazoline and its derivatives, including those bearing electron-donating or electron-withdrawing groups, can be successfully alkylated in good yields by using various C4-alkyl DHPs.

Supporting Information



Publication History

Received: 01 September 2020

Accepted after revision: 20 October 2020

Accepted Manuscript online:
20 October 2020

Article published online:
27 November 2020

© 2020. Thieme. All rights reserved

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
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