Molybdenum complexes dihydrogen

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. 

Heterolytic Cleavage of Dihydrogen by Ruthenium and Molybdenum Complexes... 

Protonation of coordinated dinitrogen with dihydrogen mediated by sulfido-bridged dinuclear molybdenum complexes... 

DIHYDROGEN MEDIATED BY SULFIDO-BRIDGED DINUCLEAR MOLYBDENUM COMPLEXES... 

H2. Hydrogen, molybdenum complex, 27 3 tungsten complexes, 27 6, 7 H2UP, Lithium dihydrogen phosphide, (LiH,P), 27 228... 

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... 

Evidence for tungsten dihydride complexes was obtained directly, as discussed above, but analogous complexes of molybdenum have not been directly observed. Indirect evidence for molybdenum dihydrides (or dihydrogen complexes) comes from the reaction shown in Equation 3.21, in which the molybdenum ketone complex heterolytically cleaves H2 in the reaction with a hindered base. 

In addition to zerovalent Group 10 metals, ansa-molybdenocene dihydride reacted with nitriles upon liberation of dihydrogen by photoirradiation (Scheme 1.21) [31]. Acetonitrile underwent oxidative addition of the C-CN bond to the molybdenum center. On the other hand, when the complex was treated with bulkier pivalonitrile, the side-on coordination complex was formed. 

M = molybdenum or tungsten R = Cy or isopropyl). Evidence for a side-on bonded dihydrogen ligand. J Am Chem Soc. 1984 106 451-452. (b) Kubas GJ. Metal Dihydrogen and a-Bond Complexes Structure, Theory and Reactivity. New York, NY Huwer Academic/Plenum Publishers 2001. 

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