ON THE REACTION OF 1-AZA-2-AZONIAALLENE SALTS WITH CARBODIIMIDES

1-Aza-2-azoniaallene cations 3, prepared in situ from germinal (chloro alkyl)azo compounds 2, react with carbodiimides 4 to give 4,5-dihydro- 5-imino-1H-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 nonconcerte d manner via cyanamidium cations 5 as intermediates. Hetero-Wagner-Mee rwein rearrangements of the primary cycloadducts 6 provide the final p roducts 7.