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Updated: Jun 5, 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-Ammonio-benzamidinium dichloride
Y M Legrand1, A van der Lee, M Barboiu
1Institut Européen des Membranes, UMR 5635, CC 047 Université de Montpellier II, Montpellier, France.
Abstract:
The crystal structure of the title compound, C(7)H(11)N(3) (2+)·2Cl(-), has been determined as part of a project focusing on the ability of the benzamidine system to form strong hydrogen bonds in aqueous media. It is commonly used as a ligand in affinity chromatography for purification and immobilization of enzymes. A twofold rotation axis runs along the axis of the cation. The orientation of the amidinium group with respect to the benzene ring is indicated by the N-C-C-C torsion angle of 40.2 (1)°. In the crystal structure, cations and anions are linked via hydrogen bonds. The chloride anion is surrounded by four ammonium cations in a tetra-hedral environment. The aromatic rings of the amidinium cations are π-stacked, with a centroid-centroid distance of 4.178 (1) Å.
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