77896-71-0Relevant academic research and scientific papers
The syntheses of 4-arylamino-1,2,3-triazoles and stable 6-sydnonyl verdazyls from sydnone derivatives and their fragments
Kuo, Wen-Fa,Lin, I.-Tzu,Sun, Shiaw-Wen,Yeh, Mou-Yung
, p. 769 - 782 (2007/10/03)
α-Chloroformylarylhydrazones 1 and α-chloroformylarylhydrazones of sydnonecarbaldehydes 3 have been prepared by a new synthetic route: α-chloroformylarylhydrazines hydrochlorides 2 reacted with corresponding carbonyl compounds. Reactions of compounds 3 with various hydrazines to give 6-sydnonyl-1,2,4,5-tetrazinan-3-ones 7 and/or carbazones 8 were also investigated. By oxidization with lead dioxide, compounds 7 were transformed to stable 6-sydnonyl-3,4-dihydro-3-oxo-1,2,4,5-tetrazin-1(2H)-yl radical derivatives 9 (sydnonyl verdazyls). Furthermore, sydnonecarbaldehydes arylhydrazones 5 through acidic conditions could be transferred to 4-arylamino-1,2,3-triazoles 6 which were also obtained by means of acidic decompositions of 4-formylsydnones 10.
Electrophilic and Nucleophilic Substitution in the Triazole N-Oxides and N-Methoxytriazolium Salts: Preparation of Substituted 1,2,3-Triazoles
Begtrup, Mikael,Holm, John
, p. 503 - 513 (2007/10/02)
2-Phenyltriazole 1-oxides are activated at C-5 towards both electrophilic and nucleophilic attack.The N-oxides can be selectively halogenated and, in turn, the halogen replaced by strong nucleophiles.On subsequent deoxygenation, the N-oxides yield halogeno-, methylthio-, and methoxy-triazoles.Methylation produces N-methoxytriazolium salts in which H-5 can be replaced by weak nucleophiles, e.g. fluoride ions.Thus fluoro-, chloro-, hydroxy-, alkoxy-, acyloxy-, amino-, substituted amino-, azido-, nitro-, mercapto-, alkylthio-, acylthio-, and cyano-substituents can be introduced in the triazole nucleus.Alternatively deprotonated N-methoxytriazolium salts react with electrophiles producing substituted triazole N-oxides.The reactions of triazole N-oxides with hydrogen chloride to give chlorotriazoles, and with acetyl chloride to give acetoxytriazoles, are explained.
