Isoxazoles from nitrile oxides and arylacetylenes. Kinetics of the reaction of p-chlorobenzonitrile N-oxide with phenyl- and mesityl-acetylene

Abstract

The reactions between p-chlorobenzonitrile N-oxide and phenyl- and mesityl-acetylene lead to isomeric 3,5-diarylisoxazoles and acetylenic oximes. The rates of formation of these isomers in carbon tetrachloride solution, and the rate of isomerization of the acetylenic oximes to the corresponding isoxazoles have been measured. In both cases, the results show that the acetylenic oxime is not the precursor of the isoxazole isolated from the reaction.