Snapshots of the ``breaking” of the H-H bond in the oxidative addition of H2 to a metal centre

Journal of Chemical Sciences

Balaji R Jagirdar1¹  Saikat Dutta¹ 

[1] Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012$$

关键词: Dihydrogen;    hydride complexes;    NMR spectroscopy;    ruthenium.;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

Three new monocationic molecular hydrogen complexes of ruthenium of the type trans-[RuCl(𝜂2-H2)(PP)2][BF4] (PP = bis-1,2(diarylphosphino)ethane, aryl = 𝑝-fluorobenzyl, benzyl, 𝑝-methylbenzyl) have been prepared by protonating the precursor hydride complexes trans-[RuCl(H)(PP)2] using HBF4.Et2O. These three dihydrogen complexes are quite stable and have been isolated in the solid state. The intact nature of the H-H bond in these derivatives has been established from the short spin-lattice relaxation times (𝑇1, 𝑚𝑠) and the observation of substantial H, D couplings in the HD isotopomers. The H-H bond distances (𝑑HH, Å) increase from 0.97 to 1.01 Å as the electron donor ability of the diphosphine ligand increases from the 𝑝-fluorobenzyl to the benzyl to the 𝑝-methylbenzyl moiety. These dihydrogen complexes constitute the initial stages of elongation of the H-H bond enroute to its cleavage along the reaction coordinate for the oxidative addition of H2 to a metal centre.

【 授权许可】

Unknown