Direct C-H Alkylation of Benzothiadiazoles via Organic Photoredox Catalysis.

J Org Chem

Green Catalysis Centre, College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China.

Published: February 2024

2,1,3-Benzothiadiazole is widely used as a privileged scaffold in pharmaceuticals and organic functional materials. Nonetheless, many current methods for the functionalization of 2,1,3-benzothiadiazole rely on preactivation, transition metal catalysts/promoters, or an elevated reaction temperature. Herein we disclose a transition-metal-free visible-light-induced photocatalytic method for the direct C-H alkylation of 2,1,3-benzothiadiazole using readily accessible carboxylic acid derivatives, i.e., -hydroxyphthalimide esters (NHPEs), as alkylating reagents under room temperature. This mild and scalable method is highlighted by the late-stage installation of the benzothiadiazole scaffold in drugs and natural products.

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http://dx.doi.org/10.1021/acs.joc.3c02307DOI Listing

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