title: Mechanistic insights into the role of PC- and PCP-type palladium catalysts in asymmetric hydrophosphination of activated alkenes incorporating potential coordinating heteroatoms.
abstract: The impact of the structural attributes of chiral PC- and PCP-palladium catalysts was investigated in the asymmetric hydrophosphination of various heterocycle-functionalized enone substrates. Due to the architecture of the catalysts, they are confronted with potential catalyst deactivation arising from the coordination of the electron-rich heteroatoms (P, O, N and S) to the metal center. A systematic variation of the location and identity of the heteroatoms demonstrated the impact of structural modifications on the substrates, which have a significant influence on both yields (16-99%) and enantioselectivities (0-99%). A detailed discussion on the distinct catalytic mechanisms (intra- vs. inter-molecular addition) provides important information to explain the results obtained.
authors.affiliation: Division of Chemistry & Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371. pakhing@ntu.edu.sg.
authors.forename: Xiang-Yuan
authors.initials: XY
authors.lastname: Yang
authors.forename: Yu-Xiang
authors.initials: YX
authors.lastname: Jia
authors.forename: Wee Shan
authors.initials: WS
authors.lastname: Tay
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Li
authors.forename: Sumod A
authors.initials: SA
authors.lastname: Pullarkat
authors.forename: Pak-Hing
authors.initials: PH
authors.lastname: Leung