aza-Michael reaction was achieved by using the combination of a bifunctional chiral Pd―μ-hydroxo complex with aromatic amine salts. The reaction proceeded smoothly to give the desired β-amino carbonyl compounds bearing a stereogenic carbon center at the α-position in good yield with excellent enantioselectivity (up to 97% ee). Although reactions with salts of electron-deficient amines were slow, the
Scope and Mechanism of Tandem Aza-Michael Reaction/Enantioselective Protonation Using a Pd-μ-Hydroxo Complex under Mild Conditions Buffered with Amine Salts
protonation of α‐substituted α,β‐unsaturated carbonylcompounds is described in detail. The key to success is the combined use of a Brønsted basic palladium–μ‐hydroxo complex and amine salts, which allows for the controlled generation of active catalyst and nucleophilic free amines. This catalytic system was applicable to various acceptors and aromatic amines, and the desired β‐amino acid derivatives