77896-57-2Relevant academic research and scientific papers
Reaction of 2-phenyl substituted 1,2,3-triazol 1-oxides with acylating agents. Preparation of hydroxy- halogen- hydroxymethyl- and chloromethyltriazoles
Begtrup, Mikael
, p. 717 - 728 (2007/10/03)
2-Phenyltriazol 1-oxides react with acetyl chloride producing acetoxy- and chloro-substituted triazoles.The substituents enter the 5 and the 4-position.When these are not accessible the substituents go to lateral positions and to the phenyl group producing acetoxymethyltriazoles and 2-halogenophenyl triazoles.Acetic anhydride reacts reluctantly while trifluoroacetic anhydride is more reactive producing trifluoroacetoxytriazoles.The reactions provide effective routes to hydroxy- and hydroxymethyltriazoles.Several mechanisms among which a cyclic one are operating.
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.
