Kinetic and mechanistic studies of carbon-to-metal hydrogen atom transfer involving Os-centered radicals: evidence for tunneling.

@article{LewandowskaAndralojc2014KineticAM,
  title={Kinetic and mechanistic studies of carbon-to-metal hydrogen atom transfer involving Os-centered radicals: evidence for tunneling.},
  author={Anna Lewandowska-Andralojc and David C. Grills and Jie Zhang and R. Morris Bullock and Akira Miyazawa and Yuji Kawanishi and Etsuko Fujita},
  journal={Journal of the American Chemical Society},
  year={2014},
  volume={136 9},
  pages={
          3572-8
        }
}
We have investigated the kinetics of novel carbon-to-metal hydrogen atom transfer reactions, in which homolytic cleavage of a C-H bond is accomplished by a single metal-centered radical. Time-resolved IR spectroscopic measurements revealed efficient hydrogen atom transfer from xanthene, 9,10-dihydroanthracene, and 1,4-cyclohexadiene to Cp(CO)2Os(•) and (η(5)-(i)Pr4C5H)(CO)2Os(•) radicals, formed by photoinduced homolysis of the corresponding osmium dimers. The rate constants for hydrogen… 
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