Issaku Yamada, Munetaka Ohkouchi, Motowo Yamaguchi and Takamichi Yamagishi
The novel chiral phosphinediamine ligand (PN2) having
two
amino units has been readily prepared from
(S)-1-phenylethylamine derivatives and
dichlorophosphine. In the hydrogenation of acrylic acids by a
rhodium–PN2 catalyst, high enantioselectivities were
achieved by the effective chiral field formed through selective P-N
chelation and electrostatic interaction between the amino unit of the
ligand and the carboxy unit of the substrate.