Author/Authors :
Danjo، نويسنده , , Hiroshi and Sasaki، نويسنده , , Wataru and Miyazaki، نويسنده , , Takehiro and Imamoto، نويسنده , , Tsuneo، نويسنده ,
Abstract :
P-Chirogenic trialkylphosphonium salts were prepared from the corresponding free phosphines by treatment with a strong acid (HBF4 or HOTf). No racemization of the phosphonium salts occurred in methanol or water even at considerably high temperature. The salts were conveniently used in rhodium-catalyzed asymmetric hydrogenation of enamides.