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Updated: Jun 12, 2026

Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants
Published on: October 19, 2017
Fluorinated Pentanidium-Enabled Enantioselective Desymmetrization of Phosphinic Acids
Yan Hu1, Huajun Li1, Jinxin Tian2
1Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
Abstract:
Catalyst design within chiral cationic phase-transfer catalysts (ccPTCs) has commonly relied on the assistance of hydrogen bonding and steric hindrance to achieve high stereochemical control. In contrast, π-hole interactions have been underutilized, despite their high potential in molecular recognition and substrate activation. Herein, we developed a π-hole-decorated pentanidium which enabled an enantioselective desymmetrization of phosphinic acids to afford chiral phosphinates in high yields and enantioselectivities. The π···π-hole interactions within the pentanidium catalyst, as well as the pentanidium-phosphinate ion pair, were supported by single-crystal X-ray crystallographic analysis and 1H-19F HOESY NMR analysis, respectively. Moreover, computational studies indicated the dynamic behavior of π-hole interactions between a pentanidium cation and phosphinate anion, which would change from initial π···π-hole interaction responsible for substrate recognition to lone pair/anion···π-hole interaction in the enantio-determining transition state.
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