2-Pyridineacetonitrile was found to react with 1,3-dichloro-2-propanone in the presence of chlorotrimethylsilane yielding 2-chloromethyl-1-indolizinecarbonitrile. The chlorine atom in the prepared indolizine was replaced by various nucleophiles including substituted anilines. Treatment of 2-(arylamino)methyl-1-indolizinecarbonitriles with hydrochloric acid resulted in 2-aryl-2,3-dihydro-1H-pyrrolo[3,4-a]indolizine-1-iminium chlorides.
alkylations - amidines - chlorotrimethylsilane - nitriles - ultrasound