Alkylazinylcarbonitriles as building blocks in organic synthesis: Synthesis of 3-amino-7-arylhyrazonothieno-7H-[3,4-c]-pyridine-4,6-diones and pyrido-[3,4-c]-pyridazine-5-carbonitrile

Abstract

A series of 5-arylhydrazono-1,2,5,6-tetrahydro-1,4-dialkyl-2,6- dioxopyridine-3-carbonitriles 4 has been prepared and reacted with elemental sulfur to yield the thieno[3,4-c]pyridine-4,6-dione 5. Reaction of 5 with dimethyl acetylenedicarboxylate afforded arylazoisoquinolines 7. Condensation of 4 with dimethylformamide dimethylacetal afforded pyrido[3,4-c]pyridazine-5- carbonitrile 9. ©ARKAT USA, Inc.