"Long-range" metal-ligand cooperation in H2 activation and ammonia-promoted hydride transfer with a ruthenium-acridine pincer complex.

@article{Gunanathan2010LongrangeMC,
  title={"Long-range" metal-ligand cooperation in H2 activation and ammonia-promoted hydride transfer with a ruthenium-acridine pincer complex.},
  author={Chidambaram Gunanathan and Boopathy Gnanaprakasam and Mark A. Iron and Linda J. W. Shimon and David Milstein},
  journal={Journal of the American Chemical Society},
  year={2010},
  volume={132 42},
  pages={
          14763-5
        }
}
The acridine-based pincer complex 1 exhibits an unprecedented mode of metal-ligand cooperation involving a "long-range" interaction between the distal acridine C9 position and the metal center. Reaction of 1 with H(2)/KOH results in H(2) splitting between the Ru center and C9 with concomitant dearomatization of the acridine moiety. DFT calculations show that this process involves the formation of a Ru dihydride intermediate bearing a bent acridine ligand in which C9 is in close proximity to a… 
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TLDR
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