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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
A second monoclinic polymorph of 4,4'-[butane-1,4-diylbis(nitrilo-methyl-idyne)]dibenzonitrile
Abstract:
The asymmetric unit of the title Schiff base compound, C(20)H(18)N(4), contains one half-mol-ecule, lying across a crystallographic inversion centre and adopting an E configuration with respect to the C=N bonds. The imino group is coplanar with the benzene ring with a maximun deviation of 0.096 (1) Å for the N atom. Within the molecule, the planar units are parallel but extend in opposite directions from the methylene bridge. In the crystal structure, neighbouring mol-ecules are linked together by weak inter-molecular C-H⋯N hydrogen bonds involving the cyano N atoms, forming R(2) (2)(10) ring motifs.
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