Bismuth Subnitrate Catalyzed Efficient Synthesis of 3,4‐Dihydropyrimidin‐2(1H)‐Ones: An Improved Protocol for the Biginelli Reaction

Abstract

Abstract An efficient synthesis of 3,4‐dihydropyrimidinones (DHPMs) using bismuth subnitrate as the catalyst for the first time from an aldehyde, β‐ketoester, and urea in acetonitrile is described. This new method consistently has the advantage of excellent yields (88–96%) and short reaction times (1.5–4 h) than do classical Biginelli reaction conditions.