
%0 Journal Article
%A Collins, David J. 
%A Hughes, Timothy C. 
%A Johnson, Wynona M. 
%T Dihydro-1,2,4-triazin-6(1<emph type="2">H</emph>)-ones. III. Oxidation Products of 1-Methyl-3-phenyl- 4,5-dihydro-1,2,4-triazin-6(1<emph type="2">H</emph>)-one
%J Australian Journal of Chemistry
%D 1999/12/03
%V 52
%N 10
%P 971-976
%K 
%R https://doi.org/10.1071/CH99047
%U https://www.publish.csiro.au/paper/CH99047 
%X 1-Methyl-3-phenyl-4,5-dihydro-1,2,4-triazin-6(1H)-one (1) undergoes aerial oxidation to give a mixture of 1- methyl-3-phenyl-1,2,4-triazin-6(1H)-one (2) and 1-methyl-3-phenyl-1,4-dihydro-1,2,4-triazine-5,6-dione (3). The dehydro derivative (2) was cleanly prepared by the oxidation of (1) with 2,3-dichloro-5,6-dicyano-1,4- benzoquinone (ddq). The dehydro derivative (2) underwent a surprising rearrangement to the triazole (12) upon oxidation with OxoneR. Several attempts at unambiguous synthesis of the &#945;-dicarbonyl derivative (3) were unsuccessful; it was obtained, together with the 1,4-dimethyl derivative (13) by methylation of 3-phenyl-1,4- dihydro-1,2,4-triazine-5,6-dione (4) with sodium hydride and methyl iodide. 
