GENERATION OF 2-SUBSTITUTED 1-ETHENYL CATIONS FROM ETHYLENEDIAZONIUM SALTS

Thermal decomposition of 2-substituted ethylenediazonium salts 1a-d produces the corresponding 1-ethenyl cations 2a-d as short-lived intermediates. The primary vinyl cation 2d or the rearranged and energetically favored analogues 3a-c of 2a-c are intercepted by chloride to give the decomposition products 4d and 5a-c, respectively. The generation of 4d and 5a-c as well as a kinetic study of the thermolysis reaction provide no indication that the elimination of nitrogen from 1a-d is occurring with the intermediate formation of cyclic cations 6 or 7.