Tungsten dihydrogens

As an experimental example of such an INS lineshape analysis, the INS spectra of the protonated isotopomer of the same tungsten dihydrogen complex W(PCy3)(CO)3( /2-H2) are presented. 

Hoff has shown that the rate of dissociation of a tungsten-dihydrogen complex is at least one order of magnitude faster than the rate of oxidative addition (H-H bond cleavage) to a dihydride complex [128]. 

Figure 7 Reaction of tungsten atoms with cyclopentane, (i and iv) Co-condensation at -196 °C (ii) Cyclopenta-diene in benzene at 60 °C and (iii) Dihydrogen at 50 atm.

Characterization of oxygen-treated carbides of molybdenum and tungsten for /i-hexane-dihydrogen reactions... 

The first known r -dihydrogen complexes, so-called non-classical hydrido complexes, were the molybdenum and tungsten compounds, M(CO)3(PR3)2(ti -H2) (M = Mo, W R = /-Pr) isolated for the first time by Kubas [35]. In order for the... 

MoH(ti5-C5H5)(CO)2(PCy3)] was more active (2 tumovers/h). Similar but water soluble tungsten and molybdenum complexes are known [223-226] which would allow the use of water as solvent for such reactions. It is noteworthy, though, that ionic hydrogenation of ketones by dihydrogen complexes has so far been observed only in non-aqueous solutions [223,227] perhaps the coordination of a ketone is disfavoured in water due to competition by H20. 

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