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Updated: Jun 1, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
4-Methyl-pyridinium 2-carb-oxy-4,5-dichloro-benzoate monohydrate
1Faculty of Science and Technology, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
Abstract:
In the structure of the 1:1 proton-transfer compound of 4-methyl-pyridine (γ-picoline) with 4,5-dichloro-phthalic acid, C(6)H(8)N(+)·C(8)H(3)Cl(2)O(4) (-)·H(2)O, determined at 200 K, the 4,5-dichloro-phthalate anions are bridged by the water mol-ecule through O-H⋯O(carbox-yl) hydrogen bonds, giving zigzag chains which extend along the c-axis direction. The 4-methyl-pyridinium cations are linked to the chains through single N-H⋯O(water) hydrogen bonds and occupy the voids within the chains in the one-dimensional structure. The anions have the common 'planar' conformation with a short intra-molecular O-H⋯O(carbox-yl) hydrogen bond.
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