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Updated: May 22, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
4,4'-Dinitro-2,2'-[propane-1,3-diylbis(iminiumylmethanylyl-idene)]diphenolate
1School of Applied Chemical Engineering, The Research Institute of Catalysis, Chonnam National University, Gwangju 500-757, Republic of Korea.
Abstract:
The title compound, C(17)H(16)N(4)O(6), is a Schiff base, which is found as a bis-zwitterion in the solid state. The geometry around the iminium N atom indicates sp(2)-hybridization. The diiminiumpropyl-ene chain is in an approximate double-gauche conformation, with average N-C-C-C torsion angles of 69.3°. The zwitterion shows strong intra-molecular N-H⋯O hydrogen bonds between the iminium N and phenolate O atom. In the crystal, bifurcated N-H⋯(O,O) hydrogen bonds assemble pairs of molecules into inversion dimers.
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