New one-pot synthesis of pyrazolo[3,4-c]pyridazine and isoxazolo[5,4-b]pyridine derivatives from potassium cyanoacetahydroxamate

摘要

The reaction of potassium cyanoacetohydroxamate 1 with ethyl 2-aryl-hydrazono-3-oxobutyrates 2 gave the unexpected pyrazolo[3,4-c]pyridazines 7 and isoxazolo[5,4-b]pyridines 10 via a one-pot reaction. A mechanistic proof is suggested to account for the products.