Simultaneous Construction of Planar and C–N Axial Chirality Ferrocenes by Pd-Catalyzed Cascade Reaction: Reciprocal Carbonyl-Carbonyl Interaction

A Pd-catalyzed cascade combining asymmetric intramolecular C–H arylation and intermolecular Buchwald-Hartwig coupling constructs ferrocenes with both planar and C–N axial chirality (75% yield, 99% ee, 15:1 d.r.). Kinetic experiments and in situ 31P NMR confirmed the sequence of the cascade reactions. Moreover, this chirality stems from n−π* interactions and sterics. These ferrocenes are converted diastereoselectively (>20:1 dr) into planar/central chiral phosphine ligands. These ligands enable Pd-catalyzed enantioselective allylic alkylation (85% yield, 97% ee).