Enantioselective Catalytic Synthesis of α‐Stereogenic Chromen‐4‐one Amino Derivatives

Abstract

AbstractDirect enantioselective synthesis of 2‐substituted chromen‐4‐ones, bearing the amino group at α‐stereogenic center with respect to the heterocycle is developed. It is based on Mannich‐type asymmetric addition of 3‐hydroxychromen‐4‐one and its analogues to N‐protected imines in the presence of available alkaloid dihydrocuprein. α‐Stereogenic chromenone amino derivatives were formed in this reactions in 81–95% yield with up to 98% ee. The chiral adducts were transformed to diverse enantiomerically enriched chromen‐4‐one functional derivatives.