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Updated: Nov 11, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Reactions of HDDA Benzynes with C,N-Diarylimines (ArCH=NAr')
Sahil Arora1, Dorian S Sneddon1, Thomas R Hoye1
1Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455 USA.
Abstract:
o-Benzynes can be utilized to construct heterocyclic motifs using various nucleophilic and cycloaddition trapping reactions. Acridines have been synthesized by capture of C,N-diarylimines with benzynes generated by classical methods (i.e., from ortho-elimination of precursor arene compounds), although in poor yields. We report here that these imines can be trapped by benzynes generated by the hexadehydro-Diels-Alder (HDDA) reaction in an efficient manner to produce 1,4-dihydroacridine products. These dihydroacridines were subsequently aromatized using MnO2 to provide structurally complex acridines.
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