Optically Active Transition-Metal Complexes. 10.1 Bifunctional Arene−Chromium−Tricarbonyl Complexes Derived from (R)-Phenylethanamine: Easily Accessible Planar-Chiral Diphosphines and Their Application in Enantioselective Hydrogenation, Hydroamination, and Allylic Sulfonation

( R )-[{α-(Dimethylamino)ethyl}-η 6 -benzene]Cr(CO) 3 is stereoselectively substituted in the ortho-position with PPh 2, P(O)Ph 2, and CO 2 R groups. After exchange of the amino group for a chloro substituent with chloroformic esters, a variety of phosphorus, nitrogen, and oxygen nucleophiles can be diastereoselectively introduced into the α-position to generate bifunctional chelating ligands. The addition of cyanide is not fully diastereospecific. The diphosphines, structurally similar to the well-known “Josiphos”-ferrocenes, are good catalysts for rhodium-catalyzed enantioselective hydrogenation, iridium-catalyzed hydroamination, and palladium-catalyzed allylic sulfonation.