Copper (II)/RuPHOX‐Catalyzed Enantioselective Mannich‐Type Reaction of Glycine Schiff Bases with Cyclic Ketimines

Abstract A Cu(II)/RuPHOX‐catalyzed enantioselective Mannich‐type reaction of glycine Schiff bases with cyclic ketimines was developed, affording chiral α,ß ‐diamino acid derivatives in good yields with moderate to good ee and dr values. This provides an efficient methodology for furnishing chiral C β ‐tetrasubstituted α,β ‐diamino acid precursors. The catalytic system is compatible with a series of substrates. In addition, an interesting nonlinear effect of the catalyst's enantiomeric composition on reaction enantioselectivity was observed. magnified image