Reaction of diazomethane with some α-substituted acrylates

The reaction of methyl -methoxy-, -acetoxy-, and -chloroacrylate with diazomethane proceeds in conformity with the -M orienting effect of the ester group. The resulting ¹-pyrazolines are converted to 3(5)-carbomethoxypyrazole at room temperature (the reaction proceeds more readily on heating).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 545–546, April, 1973.