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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
Bis[3-allyl-1-(4-cyanobenzyl)-2-methylbenzimidazolium] di-μ-bromido-bis[bromidocuprate(I)]
1Ordered Matter Science Research Center, Southeast University, Nanjing 210096, People's Republic of China.
Abstract:
The asymmetric unit of the title compound, (C(19)H(18)N(3))(2)[Cu(2)Br(4)], contains one cation and one half-anion; there is a centre of symmetry mid-way between the two Cu atoms. In the cation, the nearly planar benzimidazole ring system is oriented at dihedral angles of 75.31 (3) and 21.39 (3)° with respect to the cyano-benzyl and allyl groups, respectively. The dihedral angle between cyano-benzyl and allyl groups is 87.94 (3)°. In the crystal structure, inter-molecular C-H⋯Br hydrogen bonds link the mol-ecules. There is a C-H⋯π contact between the cyano-benzyl ring and the anion; π-π contacts also exist between the benzimidazole ring systems as well as between the anion and the cyano-benzyl ring [centroid-centroid distances = 4.024 (1) and 4.617 (1) Å, respectively].
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