Heterocyclization of α-aminonicotinonitrile: A new approach for synthesis of triazolo[1,5-a]pyridine-8-carbonitrile

Document Type : Original Article

Author

Department of Chemistry, Faculty of Science, Zagazig University,

Abstract

A new series of 1,2,4-triazolo[1,5-a]pyridine and pyrido[1,2-b]triazine was synthesized. The synthesis commenced with one-pot synthesis of pyran from 4-chlorobenzaldehyde, acetyl acetone and malononitrile in the presence of piperidine. The pyran 1 undergo ring transformation to pyridine derivatives 2 and 3 via reaction with amm.acetate and hydrazine hydrate. 1-Aminopyridine intermolecular cyclized to a new triazolo[1,5-a]pyridines 4-7 via reaction with acetic anhydride, carbon disulfide, formic acid and triethyl orthoformate. The triazine 8 was synthesized via cyclization of pyridine 1 with acetyl acetone in the presence of pyridine.A new series of 1,2,4-triazolo[1,5-a]pyridine and pyrido[1,2-b]triazine was synthesized. The synthesis commenced with one-pot synthesis of pyran from 4-chlorobenzaldehyde, acetyl acetone and malononitrile in the presence of piperidine. The pyran 1 undergo ring transformation to pyridine derivatives 2 and 3 via reaction with amm.acetate and hydrazine hydrate. 1-Aminopyridine intermolecular cyclized to a new triazolo[1,5-a]pyridines 4-7 via reaction with acetic anhydride, carbon disulfide, formic acid and triethyl orthoformate. The triazine 8 was synthesized via cyclization of pyridine 1 with acetyl acetone in the presence of pyridine.

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