A Simple and Efficient Approach to a Rigid Diphosphine Ligand Containing Two Phosphorus and Three Carbon Stereogenic Centers by Means of a Palladium Complex Promoted Asymmetric Diels−Alder Reaction

The chiral complex 2 containing an optically pure P-chiral diphosphine ligand has been prepared efficiently in three steps by the asymmetric Diels−Alder reaction between coordinated phenyldivinylphosphine on a cationic intermediate: (i) AgClO4; (ii) 1-phenyl-3,4-dimethylphosphole; (iii) HCl.