16293-42-8

Upstream product

• 118051-26-6 2-Phenyl-4-vinyloxy-2H-[1,2,3]triazole 
• 77896-55-0 4-acetoxy-2-phenyl-1,2,3-triazole 
• 77896-39-0 2-phenyl-2H-1,2,3-triazole 1-oxide 
• 77896-38-9 2-phenylhydrazonoglyoxal 1-oxime 
• 100-63-0 phenylhydrazine 
• 20672-18-8 2-(phenylhydrazono)ethanal 
• 52478-31-6 2-phenyl-4-hydroxy-1,2,3-triazole 1-oxide 

Downstream Products

• 77896-55-0 4-acetoxy-2-phenyl-1,2,3-triazole 
• 118051-26-6 2-Phenyl-4-vinyloxy-2H-[1,2,3]triazole 
• 121033-42-9 C₁₀H₁₁N₅O₃ 
• 87213-45-4 2-phenyl-4-hydroxy-5-nitro-1,2,3-triazole 
• 118051-25-5 2-phenyl-4-hydroxy-5-nitro-1,2,3-triazole 1-oxide 
• 56012-64-7 5-bromo-2-phenyl-2,3-dihydro-[1,2,3]triazol-4-one 
• 56012-65-8 5-chloro-2-phenyl-2,3-dihydro-[1,2,3]triazol-4-one 

Relevant 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

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.

HYDROXY-1,2,3-TRIAZOLES. I. SOME CHARACTERISTICS OF 4-HYDROXY-1,2,3-TRIAZOLES

Some chemical characteristics of 2-phenyl-4-hydroxy-1,2,3-triazole and the corresponding N-oxide were investigated.It was shown that the nitration and halogenation of these compounds takes place at position 5 of the triazole ring and alkylation and acylation take place at the hydroxyl group with the formation of ethers and esters.In vinyl exchange reactions with vinyl acetate the hydroxytriazole N-oxide gives the N-vinyl derivative, while the hydroxytriazole gives triazolyl vinyl ether.

Addition of Nitrite Ions to 1-Methoxy-1,2,3-triazolium Salts. Formation of Nitro and Hydroxy Substituted Triazoles

Potassium and silver nitrite add to 1-methoxy-2-phenyltriazolium salts as ambident nucleophiles to give 4-nitro- and 4-hydroxytriazoles.If unsubstituted, the latter, via nitrosation and oxidation, affords 4-hydroxy-5-nitro-2-phenyltriazole.The hydroxytriazoles add to unchanged starting material producing bistriazolyl ethers.A nitro-substituted derivative of the latter displays photochromic properties.

1,2,3-Triazoles produced from 5-Substituted N-Methoxytriazolium Salts

Five reactions, two of which are new, have been observed when 5-substituted 1-methoxy-2-phenyltriazolium salts react with nucleophiles: (i) addition to C-4 with elimination of methanol to give unsymmetrically 4,5-disubstituted triazoles; (ii) displacement of the 5-substituent followed by secondary reactions to give a symmetrically 4,5-disubstituted triazole, a 5-substituted triazole N-oxide, a 4-substituted triazole, or a disubstituted benzeneazoacetonitrile; (iii) deprotonation of the N-methoxy-group with elimination of formaldehyde; (iv) demethylation; (v) abstraction of an α-proton from a 5-alkyl group followed by nucleophilic addition and elimination of methanol to give an α-substituted 5-alkyltriazole.The reactions are of synthetic potential as a means of introducing one or two substituents in the 1,2,3-triazole system.

Electrophilic and Nucleophilic Substitution in the Triazole N-Oxides and N-Methoxytriazolium Salts: Preparation of Substituted 1,2,3-Triazoles

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.

Process for the preparation of 2-phenyl-4-hydroxy-1,2,3-triazole-1-oxides

Process for the preparation of 2-phenyl-4-hydroxy-1,2,3-triazole-1-oxides of the formula STR1 from oxime-hydrazones of the formula STR2 in which formulae R stands for an unsubstituted or substituted phenyl group.