Studies On Chiral Phosphoric Acid-Catalyzed Asymmetric Aza-Friedel-Crafts Reaction Of Indoles With Cyclic Trifluoromethyl Ketimines

The3-indolyl methanamine structural motif is embedded in numerous indolealkaloids and synthetic indole derivatives. The enantioselective aza-Friedel-Craftsreaction of indoles with imines represents a versatile strategy to construct chiral3-indolyl methanamine framwork.Recently, asymmetric transformation of cyclic trifluoromethyl ketimines hasattracted much attention, because it can lead to formation of biologically activetrifluoromethyl dihydroquinazolines.In this thesis, an enantioselective aza-Friedel-Crafts (F-C) reaction of indoleswith cyclic N-acyl ketimines has been developed. By using chiral phosphoric acidcatalysts, a wide range of enantioenriched trifluoromethyl dihydroquinazolines wereobtained in excellent yields (up to98%) with enantioselectivities (up to99%). Inaddition, our organocatalytic protocol was found to be effective for otherelectron-enriched arenes (such as pyrrole and substituted phenol). Based on thecontrol experiments, we proposed the transition state for the aza-Friedel-Craftsreaction. Finally, by a simple recrystallization, the isomer of one adduct could beobtained with excellent optical purities (ee:>99%).