Reactions of Ketones XVI. 5,5-I)imethoxy-Δ2-1,2,3-triazoline/2,2-Dimethoxy-2-aminodiazoethane Mutual Conversion

Phenylketene dimethylacetal reacts with ethyl azidoformate to give 1-ethoxyearbonyl-4-phenyl-5,5-dimethoxy-Δ²-1,2,3-triazoline (III). The behaviour of the latter and of its isomerization product, 1-phenyl-2,2-dimethoxy-2 (N-ethoxyearbonylamino)diazoethane (IV), have been investigated in detail. The results point out a triazoline III/diazoethane IV mutual conversion.