Abstract
Several 2-aryl and 2-heteroaryloxazolo[4,5-b ]pyridines were synthesised in high yields from zwitterion or hydroxyamidine derivatives
by heating in dimethylacetamide. These intermediates were generated via hetarynic
reaction with the complex base NaNH2 -t- BuONa (5:2). The same reactions were possible with quinoline derivatives.
Key words
cyclizations - heterocycles - zwitterions - pyridines - quinolines
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