On the Reaction of 1‐Aza‐2‐azoniaallene Salts with Carbodiimides

Abstract

Abstract 1‐Aza‐2‐azoniaallene cations 3 , prepared in situ from geminal (chloroalkyl)azo compounds 2 , react with carbodiimides 4 to give 4,5‐dihydro‐5‐imino‐1 H ‐1,2,4‐triazolium salts 7 . An X‐ray structural analysis was carried out for 71 . According to AM1 calculations the cycloaddition of carbodiimides to 1‐aza‐2‐azoniaallene cations occurs in a nonconcerted manner via cyanamidium cations 5 as intermediates. Hetero‐Wagner‐Meerwein rearrangements of the primary cycloadducts 6 provide the final products 7 .