‡ These authors contributed equally to this work.
A new efficient synthesis of pyrrolidin-2-ones via sequential Wittig reaction/nucleophilic
addition/cyclization was developed. The Wittig reaction of the phosphoranes with isocyanates
produced ketenimine intermediates that were then treated with primary amines to give
amidines, which were treated with catalytic sodium alkoxide to give 2-imino-5-oxopyrrolidine-3-carboxylates
in good yields.
Key words
pyrrolidin-2-one - Wittig reaction - ketenimine - amidine - isocyanate