Mild and efficient synthesis and base-promoted rearrangement of novel isoxazolo[4,5- b]pyridines

Vladislav V Nikol'skiy; Mikhail E Minyaev; Maxim A Bastrakov; Alexey M Starosotnikov

doi:10.3762/bjoc.20.94

Mild and efficient synthesis and base-promoted rearrangement of novel isoxazolo[4,5- b]pyridines

Beilstein J Org Chem. 2024 May 14:20:1069-1075. doi: 10.3762/bjoc.20.94. eCollection 2024.

Authors

Vladislav V Nikol'skiy¹, Mikhail E Minyaev¹, Maxim A Bastrakov¹, Alexey M Starosotnikov¹

Affiliation

¹ N.D. Zelinsky Institute of Organic Chemistry RAS, Leninsky prosp. 47, 119991 Moscow, Russia.

Abstract

An efficient method for the synthesis of isoxazolo[4,5-b]pyridines has been developed on the basis of readily available 2-chloro-3-nitropyridines via the intramolecular nucleophilic substitution of the nitro group as a key step. The previously unknown base-promoted Boulton-Katritzky rearrangement of isoxazolo[4,5-b]pyridine-3-carbaldehyde arylhydrazones into 3-hydroxy-2-(2-aryl[1,2,3]triazol-4-yl)pyridines was observed.

Keywords: 1,2,3-triazoles; Boulton–Katritzky rearrangement; aromatic nitro compounds; isoxazolo[4,5-b]pyridines; nucleophilic substitution.