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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
N,N'-Bis(5-bromo-2-hydroxy-benzyl-idene)-2,2-dimethylpropane-1,3-diamine
Abstract:
The crystal structure of the title Schiff base compound, C(19)H(20)Br(2)N(2)O(2), contains two crystallographically independent mol-ecules (A and B) in the asymmetric unit, with similar conformations. Intra-molecular O-H⋯N (× 4) and C-H⋯N (× 5) hydrogen bonds form six- and five-membered rings, producing S(6) and S(5) ring motifs, respectively. One of the N atoms in mol-ecule A acts as a trifurcated acceptor, the rest of the N atoms being bifurcated acceptors. The dihedral angles between the benzene rings in mol-ecules A and B are 47.83 (17) and 61.11 (17)°, respectively. The mol-ecular conformation is stabilized by intra-molecular O-H⋯N and C-H⋯N hydrogen bonds. The short distances between the centroids of the benzene rings [3.7799 (19)-3.890 (2) Å] indicate the existence of π-π inter-actions. In addition, the crystal structure is further stabilized by an inter-molecular C-H⋯O hydrogen bond, C-H⋯π inter-actions, and short inter-molecular Br⋯Br and Br⋯O contacts [3.4786 (5) and 3.149 (3) Å, respectively].
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