Synthesis of isoxazole derivatives by means of O-acylation of aliphatic nitro compounds in the presence of acetylenic compounds.

Abstract

O-Acylation of some aliphatic nitro compounds or their alkali metal salts with acid chlorides in N, N-dimethylacetamide in the presence of acetylenic compounds afforded isoxazole derivatives in fairly good yield. The reaction is shown to arise from 1, 3-dipolar cycloaddition of acetylenic compounds to the nitrile oxide intermediates which would resulted from the fragmentation of the initially formed O-acylated product.