FeCl3-mediated three-component cascade reaction: an effective approach to the construction of highly functionalized pyrrolo[1,2-c]quinazolinones

Abstract

An unexpected FeCl3-mediated three-component cascade reaction has been used to construct structurally diverse pyrrolo[1,2-c]quinazolinone derivatives with potential biological activities. This method has advantages of mild conditions, simple work-up, as well as wide substrate scope, which makes it a powerful approach to the synthesis of diverse pyrrolo[1,2-c]quinazolinones. This cascade reaction involves 1,3-dipolar cycloaddition between azomethine ylides and allenoates, followed by intramolecular nucleophilic addition in the presence of FeCl3. The obtained products could be easily transformed into derivatives with the pyrrolo[2,3-c]quinazoline alkaloid skeleton.

Keywords: allenes; azo compounds; domino reactions; fused-ring systems; iron.