Ir/Cu Dual Catalysis: Enantio- and Diastereodivergent Access to α,α-Disubstituted α‑Amino Acids Bearing Vicinal Stereocenters

We describe a fully stereo­divergent synthesis of a range of α,α-disubstituted α-amino acids via an Ir/Cu-catalyzed α-allylation of readily available imine esters. The introduction of a Cu-Phox complex-activated imine ester into the chiral iridium-catalyzed allylic allylation process is crucial for its high reactivity and excellent enantio- and diastereo­selectivity (up to >99% ee and >20:1 dr). Importantly, the two chiral catalysts allow for full control over the configuration of the stereo­centers, affording all stereo­isomers of the desired products. The utility of this methodology was demonstrated by synthesizing dipeptides and analogues of bioactive molecules in a stereo­divergent manner.