Catalytic asymmetric 1,6-type Friedel–Crafts (hetero)arylations of δ-Cyano substituted para-quinone methides with 5-aminopyrazoles

Abstract

Triarylmethanes is a privileged motif in numerous biologically significant natural molecules and materials. Herein, we achieved a highly efficient enantioselective 1,6-type Friedel–Crafts (hetero)arylations of δ-Cyano substituted para-quinone methides with 5-aminopyrazoles. This method enabled the precise synthesis of chiral triarylmethanes with a cyanide-substituted all-carbon quaternary center, with high yields and exceptional enantioselectivities (up to 92% ee) for the majority of substrates.