Oxidation of 1,1-disubstituted hydrazines with benzeneseleninic acid and selenium dioxide. Facile preparation of tetrazenes

Article abstract of DOI:10.1139/v82-390

Various 1,1-disubstituted hydrazines were oxidized with benzeneseleninic acid in methanol, generally producing the corresponding tetrazenes in high yield.Studies of the by-products of the reaction, of the effects of protic vs. aprotic solvents, and trapping experiments suggest that N-aminonitrenes are unlikely intermediates in this oxidation.An alternative mechanism involving a Pummerer-like reaction of seleninamides derived from the hydrazines is proposed.Tetrazene formation fails when the hydrazine precursor contains an aryl or p-toluenesulfonyl substiuent, or when it is highly hindered.Selenium dioxide may be employed as the oxidant instead of the seleninic acid, but is generally less efficacious in achieving high tetrazene yields.