Reaction of 5-aminopyrazole derivatives with ethoxymethylene- malononitrile and its analogues

Article abstract of DOI:10.1002/jhet.5570310140

A one-pot synthesis using 5-aminopyrazole derivatives 1 with ethoxymethylenemalononitrile (EMMN), ethyl ethoxymethylenecyanoacetate (EMCA) or diethyl ethoxymethylenemalonate (DEMM) gave pyrazolo-[1,5-a]pyrimidine compounds 2,4,8. Also, the one step reaction of EMCA with hydrazine hydrate afforded ethyl(4-ethoxycarbonyl-5-pyrazolyl)aminomethylenecyanoacetate 3c. On the other hand, the reaction of 1-substituted 5-aminopyrazole-4-carboxamide 9 with EMMN afforded pyrazolo[3,4-d]pyrimidine compounds 10.