Acyclic Trialkyldiazenium Cation Chemistry. Thermolysis and Solvolysis of 1,2-Di-tert-butyl-1-ethyldiazenium Perchlorate

Article abstract of DOI:10.1021/ja00384a030

The thermolysis, ethanolysis, and ethanolysis with 2,6-lutidine reactions of 1,2-di-tert-butyl-1-ethyldiazenium perchlorate (3) are reported.Clean first-order kinetics were observed for these reactions.The reactivity of 3 was found to be nearly the same for the various reaction conditions.Thermolysis of 3 yielded acetaldehyde tert-butylhydrazonium perchlorate (4) and isobutylene (5) as products.Ethanolysis gave 4, 5, ethyl tert-butyl ether (6), acetaldehyde diethyl acetal (7), and mono-tert-butylhydrazinium perchlorate (8).For ethanolysis with lutidine, the products were 5, 6, 7, trans-1,1-dimethylazoethane (10), and 1,2-di-tert-butylhydrazinium perchlorate (11).The kinetic and product results for both thermolysis and ethanolysis are rationalized by a mechanistic sequence involving as key first steps a prototropic rearrangement of diazenium cation 3 to an iminium cation 14, which subsequently ionizes to tert-butyl cation (13) and acetaldehyde tert-butylhydrazone (12).For ethanolysis with lutidine, two separate competing mechanistic processes are indicated.One pathway involves direct ionization of 3 to 10 and 13.The second pathway involves the rearrangement of 3 to 14 followed by direct reaction of 14 with ethanol.