Copper(I)‐Catalyzed Conjugate Addition/Enantioselective Protonation with Selenols and α‐Substituted α,β‐Unsaturated Thioamides

Abstract

AbstractHerein, a copper(I)‐catalyzed asymmetric conjugate addition/protonation with selenols and α‐substituted α,β‐unsaturated thioamides is disclosed, which affords a series of chiral selenides in high to excellent enantioselectivity. As for both selenols and α‐substituted α,β‐unsaturated thioamides, the reaction enjoys broad substrate scopes. The present catalytic system is also successfully applied to asymmetric selenation of β‐substituted α,β‐unsaturated thioamides. A [Cu‐(R,RP)‐TANIAPHOS]‐SePh species is characterized by its 77Se NMR spectra, which gives a chemical shift at δ 462 ppm. Moreover, a {[Cu‐(R)‐TOL‐BINAP]‐SePh}2 species is characterized by X‐ray analysis, which confirms the formation of Cu−Se bond in the reaction. Finally, the transformations of the thioamide group to amine and thioester are demonstrated to be straightforward.