1,2,4-Triazolium Salts from the Reaction of 1-Aza-2-azoniaallene Salts with Nitriles

Synthesis of 3′‐1,2,4‐triazolo‐ and 3′‐1,3,4‐thiadiazoliminothymidines

“…Analogously, the heteroallene 7 carrying a tert-butyl group were used to synthesize neutral 2-substituted 1,2,4-triazoles [30,31]. Compounds 7, which formed at low temperature from 6 [15,18] and SbCl 5 , reacted with the isothiocyanate 9 via C S cycloaddition to give the nitrilium ion 13a as an intermediate.…”

“…• C, 20a-c rearranged spontaneously by migration of the alkyl group at C-3 , via [1,2-shift] [30,34] to N-2 accompanied by the elimination of the CClR 1 R 2 group at N-1 , leading to the protonated 1,2,4-triazolium salts 21a-c. In situ deprotonation with aqueous NaHCO 3 [30,31] 33 were attributed to the methyl groups at C-5 of the triazole ring.…”

Synthesis and anti‐HIV activity of substituted 1,2,4‐triazolo‐thiophene derivatives

“…In our recent work, these cations have been utilized in the synthesis of new types of 1,2,4-triazoles such as C-nucleosides [14,15], acyclic C-nucleosides [16], pyrimidines [17], N-alkylphthalimides [18], D-mannopentitol-1-yl-1,2,4-triazoles [19], 1H-indoles [20], quinolones [20], benzotriazoles [21], 3 -triazolo-thymidines [22], acetic acid alkylidene hydrazides [23], and 1,4-disubstituted piperazines [24,25]. The reactive intermediates (4) were obtained from the α,α -dichloroazo compounds 3 [13] by treatment with SbCl 5 at −60…”

New benzylpiperazine derivatives bearing mono‐ and bis‐dialkyl substituted 1,2,4‐triazoles

“…• C, 4 rearranged to protonated triazole 5 by [1,2] migration [39,40] Next, condensation of 6a-d with piperazine in the ratio of (2:1) in the presence of NaH or K 2 CO 3 and DMF at 25…”