A highly efficient one-pot conversion of β-aminocrotononitrile to secondary enaminonitriles including chiral ones is described. In contrast to β-aminocrotononitrile, some of these N- substituted β-enaminonitriles on reacting with acid chlorides show a unique preference for C- terminal selection allowing preparation of pyrazoles without separation of regioisomers. In addition, use of secondary enaminonitriles also provided access to pyrazoles that are not ...
