A simple protocol for the synthesis of chiral bidentate imidodiphosphoric tetramide ligands: application in the metal-free asymmetric allylation of aldehydes

The reaction of a series of chiral phosphorus triamides with BuLi and subsequent addition of a phosphoroxychloride diamide afforded the corresponding imidodiphosphoric tetramides in high yield. The use of enantiomerically pure diamides allowed access to bidentate imidodiphosphoric tetramides without loss of optical purity. These bidentate ligands have been used successfully to catalyze the addition of allyltrichlorosilane to aldehydes in an enantioselective fashion up to 60% ee.