51039-50-0

Upstream product

• 56530-30-4 1,2-bis-phenylazo-propene 
• 7707-85-9 pyruvaldehyde bis-phenylhydrazone 
• 77896-41-4 4-methyl-2-phenyl-2H-[1,2,3]triazole 1-oxide 
• 27607-77-8 trimethylsilyl trifluoromethanesulfonate 
• 5188-07-8 sodium thiomethoxide 
• 7647-01-0 hydrogenchloride 
• 41350-48-5 2-phenylazopropene 
• 1875-48-5 N-aminophthalamide 
• 38482-38-1 methylglyoxal 2-oxime 1-phenylhydrazone 
• 5391-74-2 1-(phenylhydrazono)-propan-2-one 
• 100-63-0 phenylhydrazine 
• 85322-82-3 5-methyl-2-phenyl-1,2,3-triazole 1-oxide 
• 108-24-7 acetic anhydride 
• 6017-59-0 3-methyl-4-phenylhydrazonoisoxazol-5-one 

Downstream Products

• 13322-05-9 2-(4-bromo-phenyl)-4-methyl-2H-[1,2,3]triazole 
• 13306-99-5 2-phenyl-2H-[1,2,3]triazole-4-carboxylic acid 
• 27200-07-3 4-methyl-2-(4-nitrophenyl)-2H-1,2,3-triazole 

Relevant academic research and scientific papers

Synthesis of 2-Substituted 1,2,3-Triazoles via an Intramolecular N–N Bond Formation

An efficient synthesis of 2-aryl 1,2,3-triazoles based on an intramolecular N–N bond formation is described. Selective activation of bis-hydrazone at the dimethylamino hydrazone group with MeI forms a mono-hydrazonium species. Treatment of the hydrazonium

Cu-Mediated Expeditious Annulation of Alkyl 3-Aminoacrylates with Aryldiazonium Salts: Access to Alkyl N2-Aryl 1,2,3-Triazole-carboxylates for Druglike Molecular Synthesis

Alkyl N-aryl 1,2,3-triazole-carboxylates are important molecules or intermediates in medicinal chemistry, but the synthesis of N2-aryl counterparts remains elusive. Herein, we describe a Cu-mediated annulation reaction of alkyl 3-aminoacrylates with aryldiazonium salts, both of which are readily available substrates. Furthermore, alkyl 2-aminoacrylates are also viable substrates. Diverse alkyl N2-aryl 1,2,3-triazole-carboxylates and their analogues can be rapidly prepared under mild conditions. Especially, this protocol allows one to access several druglike variants of carbonic anhydrase inhibitors and celecoxib.

Oxidation of N-aminophthalimide in the presence of conjugated azoalkenes: Azimines, azoaziridines, and [1,2,3]triazoles

The oxidation of N-aminophthalimide (1) with lead tetraacetate in the presence of the phenylazoalkenes 2 afforded 2-phenylazo-1-(N-phthalimido)aziridines 3 or 2-phenyl[1,2,3]-triazoles 7, as well as phthalimide (4). The reaction of 2-phenylazo-1-propene (2d) produced 5-methyl-2-phenyl-[1,2,3]triazole (7d) and N-[2-(phenylhydrazono)propylidene-amino]phthalimide (8d). The cyclic azoalkene 3,3,5-trimethyl-3H-pyrazole (11) gave a mixture of (Z)-3,3,5-trimethyl-1-[N-(phthalimido)amino]-3H-pyrazol-1-ium-2N-ide [(Z)-12] together with the regioisomers (E)- and (Z)-3,3,5-trimethyl-1-[N-(phthalimido)amino]-3H-pyrazol-2-ium-1N-ides [(E)- and (Z)-13].

Oxidative addition of N-aminophthalimide to conjugated azoalkenes. Synthesis of the first C-azoaziridines

The oxidation of N-aminophthalimide with lead tetraacetate in the presence of β-phenylazostyrene or 1-phenylazocyclohexene results in phenylazo-1-phthalimidoaziridines, the first among derivatives of C-azoaziridines. 1-Phenylazopentene yields quite different product, 2-phenyl-2,4,5,6-tetrahydrocyclopenta[d]-1,2,3-triazole. From 2-phenylazapropene was obtained a mixture of the corresponding triazole and N-[2-(phenylhydrazono)propylidenamino]phthalimide, but the same reaction with the cyclic azoalkene, 3,3,5-trimethyl-3H-pyrazole, afforded the mixture of three regio and stereoisomeric phthalimidoazimines.

Silylation of Azole N-Oxides

Pyrazole N-oxides and 1,2,3-triazole-N-oxides can be C-silylated at ring exocyclic α-positions in high yields in a one-pot procedure by treatment with trimethylsilyl triflate, trimethylsilyl iodide or tert-butyldimethylsilyl triflate in the presence of 1,

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.