
%0 Journal Article
%A Clark, Adrian D. 
%A Ha, Uyen T. 
%A Prager, Rolf H. 
%A Smith, Jason A. 
%T High-Temperature Rearrangements of 2-Acylisoxazol-5(2<emph type="2">H</emph>)-ones and Related Oxazoles.
%J Australian Journal of Chemistry
%D 2000/02/04
%V 52
%N 11
%P 1029-1034
%K 
%R https://doi.org/10.1071/CH99075
%U https://www.publish.csiro.au/paper/CH99075 
%X 2-Acyl-3-arylisoxazol-5(2H)-ones give 2-alkyl(aryl)-4-aryloxazoles in good yields at 540&#176;C under flash vacuum pyrolysis conditions, but at higher temperatures the expected oxazoles are accompanied by increasing amounts of isomeric 2,5-disubstituted oxazoles, as well as anilides and decomposition products of the 2,4-disubstituted oxazole. The rearrangement mechanisms have been studied by the use of 13C labelled substrates and p-substituted 3-arylisoxazolones. The 2,5-disubstituted oxazoles are considered to arise from 1H-azirines, and the anilides from the nitrone ketene isomer of the acylisoxazolone. 
