Readily Available Biaryl P,N Ligands for Asymmetric Catalysis

A short and modular synthesis of novel P,N ligands (pinap; see scheme; X=O or NH) is presented. A covalently bound chiral group allows the separation of the atropisomeric diastereomers, thus avoiding resolution involving chiral Pd–amine complexes. The utility of the ligands is demonstrated for three reactions catalyzed by different transition metals; in each case products are obtained with high enantiomeric excess (up to 99 % ee).