Asymmetric Synthesis of Triphenylmethanes via Organocatalytic Regio- and Enantioselective Friedel–Crafts Alkylation of Aniline Derivatives

Herein, we described a highly regio- and enantioselective
Friedel–Crafts
alkylation of aniline derivatives with in situ generated ortho-quinone methides enabled by chiral phosphoric acid,
furnishing a wide range of enantioenriched triarylmethanes bearing
three similar benzene rings in high yields (up to 98%) with excellent
stereoselectivities (up to 98% ee). Furthermore, the large-scale reactions
and diversified transformations of product demonstrate the practicality
of the protocol. Density functional theory calculations elucidate
the origin of the enantioselectivity.