Polyfunctional Nitriles in Organic Syntheses: A Novel Route to Aminopyrroles Pyridazines and Pyrazolo34-cpyridazines

摘要

Phenacylmalononitrile >1 reacts with dimethylformamide dimethyl acetal to yield an enaminone which could be readily converted into a pyrrole or an aminopyridazine by treating with ammonium acetate and hydrazine hydrate, respectively. Compound >1 reacted with hydrazine hydrate in ethanol at room temperature to yield the dihydropyridazine >9 as a single product. In refluxing ethanol this product further reacted with hydrazine hydrate to yield the novel dihydropyrazolopyridazinamine >10.