Synthesis of Tricyclic 1,2,3-Triazolopyridines

Abstract

Novel tricyclic triazolopyridines were prepared in two steps from the requisite bicyclic 2-ketopyridines. In order to examine the scope of the process, a reliable route to the 2,3-dihydro-1,5-naphthyridin-4(1H)-one, 7,8-dihydro-5H-pyrido[3,2-b]azepin-9(6H)-one, 7,8-dihydrooxepino[3,2-b]pyridin-9(6H)-one, and 7,8-dihydro-5H-pyrido[3,2-c]azepin-9(6H)-one scaffolds was also established.

Key words

heterocycles - triazolopyridines - 2-acylpyridines - hydrazones - N–N bond formation

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