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Updated: Dec 3, 2025
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Chiral Electron-Rich PNP Ligand with a Phospholane Motif: Structural Features and Application in Asymmetric
Heng Wang1,2, Yao Zhang1, Tilong Yang1
1Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.
Abstract:
Despite the remarkable reactivity that was achieved by a series of transition-metal catalysts with a PNP type ligand, the electron-rich chiral PNP ligands have still been rarely reported because of the difficulties in synthesis and the nature of air-sensitivity. Herein, we report a novel chiral PNP ligand (Heng-PNP) with both a rigid backbone and a bulky tert-butyl group on the phospholane motif. We successfully obtained its divalent iron complex. The chiral environment of its Ir(III) complex was also discussed with quadrant analysis. This tridentate ligand was applied in iridium-catalyzed asymmetric hydrogenation of challenging diaryl ketones: up to 98% ee and 500 TON are achieved. Computational study showed that the twist of conjugate aryl group in the substrate (induced by the special chiral pocket of Ir/Heng-PNP complex) leads to the energy difference in the enantiodetermining step.
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