Oxidative C(sp)-H functionalization of methyl-azaheteroarenes: a facile route to 1,2,4-triazolo[4,3-a]pyridines.

Org Biomol Chem

School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai, 264005, P. R. China.

Published: February 2019

We herein describe an oxidative [4 + 1] annulation used to prepare 1,2,4-triazolo[4,3-a]pyridines in the presence of I2-DMSO. This protocol enables synthesis of triazolo[4,3-a]pyridine-quinoline linked diheterocycles via a direct oxidative functionalization of sp3 C-H bonds of 2-methyl-azaheteroarenes. The reaction shows a wide substrate scope and good functional group tolerance.

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http://dx.doi.org/10.1039/c9ob00033jDOI Listing

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