1,2,4-Triazolium salts from the reaction 1-aza-2-azoniaallene salts with nitriles
Aryl- and alkylhydrazones 1 of alkyl ketones and propanal are transformed to 1-chloroalkylazo compounds 2 with tert-butyl hypochlorite. Compounds 2 react with antimony(V) chloride or aluminum(III) chloride to give 1-aza-2-azoniaallene salts 3 as reactive