Asymmetric Synthesis of Functionalized 1,2-Diphosphine via the Chemoselective Hydrophosphination of Coordinated Allylic Phosphines
datasetposted on 09.02.2009, 00:00 by Mingjun Yuan, Sumod A. Pullarkat, Mengtao Ma, Yi Zhang, Yinhua Huang, Yongxin Li, Akash Goel, Pak-Hing Leung
Ester- and keto-functionalized allylic monophosphine palladium complexes containing ortho-metalated (R)-(1-(dimethylamino)ethyl)naphthalene as the chiral auxiliary were synthesized via a versatile one-pot process. Subsequent asymmetric hydrophosphination of the coordinated allylic substrates promoted by the chiral auxiliary gave the corresponding functionalized chiral 1,2-bis(diphenylphosphino)ethane ligands in high yields under mild conditions. The coordination properties and absolute configurations of the resultant diphosphine ligands were established by single-crystal X-ray crystallography. The coordinated 1,2-diphosphine ligands could be subsequently liberated stereospecifically to yield enantiomerically pure functionalized diphosphines in high yields.