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Updated: Dec 23, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Organocatalysis by Halogen, Chalcogen, and Pnictogen Bond Donors in Halide Abstraction Reactions: An Alternative to
Ying Li1, Lingpeng Meng1, Cuihong Sun2
1Institute of Computational Quantum Chemistry, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang 050024, P.R. China.
Abstract:
The application of σ-hole interactions (halogen, chalcogen, and pnictogen bonds) in organocatalysis has attracted more and more interest in recent years. The catalysis mechanism of halogen, chalcogen, and pnictogen bonds in the chloride abstraction from Reissert-type substitution of isoquinoline has been investigated by the density functional theory. Compared with the reaction without catalysts, the reactions catalyzed by the σ-hole interactions have lower energy barriers and are more favorable. The formation of the σ-hole interaction between the Cl atom and halogen, chalcogen, and pnictogen bond donors facilitates the chloride abstraction reaction by weakening the strength of the C-Cl bond and decreasing the HOMO-LUMO gap of the reactants. The catalytic activity follows the sequence of pnictogen bonds > chalcogen bonds > halogen bonds and shows an increase from period 3 to 5 in the same group, and pnictogen bond donors, especially tris (pentafluorophenyl) antimony, show the best catalysis performance.
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