Abstract
2-Cyanoacetyl-1-methylpyrrole 1 reacts with acetylacetone in glacial acetic acid in presence of ammonium acetate to yield a polysubstituted pyridine derivative 5. In contrast, ethyl acetoacetate reacts with 1 to yield a pyranone derivative 8, formed via a rearrangement process. Enaminonitrile 3, generated by reaction of 2-cyanoacetyl-1-methylpyrrole 1 with the dimethylformamide dimethylacetal (DMFDMA), undergoes condensation with malononitrile to yield a 2-dialkyl-aminopyridine again via a rearrangement pathway. Structural assignments to 2-cyanoacetyl-1-methylpyrrole 1, enaminonitrile 3, pyrrole-substituted pyran 8, and pyridine 14 were made using X-ray crystallographic analysis. Finally, 2-cyanoacetyl-1-methylpyrrole 1 undergoes coupling with benzenediazonium chloride to yield the arylhydrazone 2 that reacts with hydroxylamine hydrochloride to yield an amidoxime 19 that participates in ready cyclization to form the pyrrole-substituted 1,2,3-triazole 20 whose structure could be also established by X-ray crystallography.