Chiral Spirocyclic Phosphoric Acid‐Catalyzed Synthesis of 4‐Alkyl‐3,4‐dihydropyrimidin‐2(1H)‐one Derivatives by Asymmetric Biginelli Reactions

Abstract

AbstractA chiral spirocyclic phosphoric acid‐catalyzed asymmetric Biginelli reaction based on aliphatic aldehydes has been realized for the synthesis of biologically important and synthetically useful 4‐alkyl‐3,4‐dihydropyrimidin‐2‐(1H)‐one (4‐alkyl−DHPM) skeletons in good yield and with high levels of enantioinduction. The utility of this transformation was further demonstrated by direct thionation and C−C/C−N bond construction to provide a series of 4‐alkyl−DHPMs derivatives without any loss of optical activity, providing streamlined access to the formal synthesis of Batzelladine A.