The reaction of N-alkenylamides with benzeneselenenyl halides affords pyrrolidine or piperidine derivatives through the cyclization by a nitrogen atom of the amide group induced by the addition of a phenylseleno group to the double bond. The introduction of substituents into the carbon atom between the double bond and amide moiety facilitates the cyclization reaction. The effect of a halide ion of the selenenylating reagent is also significant, ...
