1- Alkyl-1.2,3-triazolium salts, ring

Dihydro-1,2,4-triazines 95 were obtained by base-indueed ring expansion of 1-alkyl-1,2,3-triazolium salts, and their strueture in the solid state was eonfirmed by X-ray analysis [92JCS(P1)147]. 

Disubstituted triazolium salts are prepared from alkyl or aryl hydrazines via an oxadiazolium salt 28 (Scheme 16). Addition of a chiral amine on this salt resulted in a ring opening - ring closure reaction affording the triazolium salts 29. 

The syntheses of 1,2,3-triazolium salts consists of two major steps, which are construction of the 1,2,3-triazole ring system and then its N-alkylation (Scheme 1). While l-amino-1,2,3-... 

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