Oxime derivatives of 5-oxoalkanenitriles (Ce chain or longer) were cyclized in most cases with a combination of AcCl and AczO, or AcgO and HC1 to 6-substituted 2-(N-acetylamino)pyridines. Alkaline hydrolysis gave the corresponding 2-aminopyridines in overall yields of 40-65%, with the éxception of pyridine 3e. Oxime derivatives of 5-oxopentanenitriles did not cyclize but gave glutaronitriles instead. In some experiments with 5-oximinohexanenitrile (la), 2,4-dimethyl-5-(2-cyanoethyl)oxazole ( 9) was detected in addition to the main product, 2-(IV-acetylamino)-6-methylpyridine (2a). Formation of these compounds can be explained on the basis of a common intermediate 7 formed through rearrangement of the O-acetylated 5-oximinohexanenitrile (4).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.