V. Matiichuk, M. A. Potopnyk, N. D. Obushak
Oct 12, 2008
Citations
1
Influential Citations
31
Citations
Journal
Russian Journal of Organic Chemistry
Abstract
Reactions of arenediazonium chlorides with ethyl 2-methyl-and 2-chloro-4-oxobutanoates gave, respectively, ethyl 2-(arylhydrazono)propanoates and chloro(arylhydrazono)acetates. Ethyl 2-(arylhydrazono)-propanoates reacted with the Vilsmeier-Haak reagent to give ethyl 1-aryl-4-formyl-1 H-pyrazole-3-carboxylates. Ethyl 1-aryl-4-acetyl-5-methyl-1H-pyrazole-3-carboxylates were obtained by reaction of chloro(arylhydrazono) acetates with acetylacetone. Reactions of the obtained pyrazole derivatives with hydrazine and methylhydrazine led to the formation of the corresponding 3,4-R21-6-R2-2-aryl-2,6-dihydro-7H-pyrazolo-[3,4-d]pyridazin-7-ones (R1, R2 = H, Me) which were subjected to alkylation and sulfurization.