311786-71-7

Upstream product

• 311786-70-6 (5-methyl-7-phenyl-2,5-dihydro[1,2,3]triazolo[4,5-d]pyridazine-4-ylidene)-pyridin-2-yl-amine 
• 311786-67-1 (5-methyl-2-(4'nitrophenyl)-7-phenyl-2,5-dihydro[1,2,3]triazolo[4,5-d]pyridazine-4-ylidene)-pyridin-2-yl-amine 
• 311786-69-3 2-(4'-nitrophenyl)-5-methyl-7-phenyl-2,5-dihydro[1,2,3]triazolo[4,5-d]pyridazin-4-one 

Relevant academic research and scientific papers

Selectivity of methylation of some new [1,2,3]triazolo[4,5-d]pyridazines and structure elucidation by 1H-15H NMR spectroscopy

Alkylation of some selected [1,2,3]triazolo[4,5-d]pyridazines having five or more nitrogen atoms capable for alkylation was investigated. Pyridyl derivatives substituted also on the [1,2,3]triazole ring gave quaternary pyridinium salts, whereas in the case of the analogues compounds unsubstituted at the triazole moiety, the alkylation of the triazole ring was also observed. Unambiguous structure elucidation was provided by 1H-15N HMBC experiments which also allowed the assignment of the 15N NMR shifts.

An unexpected valence bond isomerization to the heteroaromatic ring system: [1,2,3]triazolo[4,5-d]pyridazine

The arylazo substituted salt 2 when treated with a base underwent a valence bond isomerization to yield a derivative of the heteroaromatic ring system, [1,2,3]triazolo[4,5-d]pyridazine (4).