Diruthenium complex, hydrogen bonding

A similar rapid exchange of bridging and terminal hydride ligands and the hydrogen atoms in Ru-H-Si 3c-2e bonds is observed in the C-type diruthenium complexes Cp Ru(ju.- T2-HSiR2) 2(Ju,-H)(H) (R = Et, Ph) [see Eq. (13)].38 In these complexes, all the four hydride ligands are equivalent in the H NMR spectrum at 25°C, whereas they separate to three signals... 

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