Polyhydride complexes, transition

Bayse, C.A. and Hall, M.B. (1999) Prediction of the Geometries of Simple Transition Metal Polyhydride Complexes hy Symmetry Analysis. Journal of the American Chemical Society, 121, 1348-1358. 

Generation of Reactive Intermediates via Photolysis of Transition-Metal Polyhydride Complexes... 

The photochemical properties of several transition metal polyhydride complexes are described. Irradiation of [MoH Cdppe) ] (dppe =... 

A number of studies have demonstrated that photolysis of transition metal di- and polyhydride complexes can lead to the generation of very reactive intermediates, generally via photo-induced loss of H9 Cl, 2). Two such examples are shown in eqs 1 (3) and 2 (4-8). Z... 

The photochemical studies of transition metal hydride complexes that have appeared in the chemical literature are reviewed, with primary emphasis on studies of iridium and ruthenium that were conducted by our research group. The photochemistry of the molybdenum hydride complexes Mo(tj5-C5H5)2M2] and [MoH4(dppe)2] (dppe = Ph2PCH2CH2PPh2), which eliminate H2 upon photolysis, is discussed in detail. The photoinduced elimination of molecular hydrogen from di-and polyhydride complexes of the transition elements is proposed to be a general reaction pathway. 

Mo(r75-C5H5)2H2] and [MoH dppe ]. Our studies of the di- and trihydride complexes of ruthenium and iridium, described above and published previously (27,35), and those of other workers (discussed at the beginning of this chapter), indicate that photoinduced elimination of molecular hydrogen is a common reaction pathway for di- and polyhydride complexes. To demonstrate the photoreaction s generality and its utility for generating otherwise unattainable, extremely reactive metal complexes, we have begun to study the photochemistry of polyhydride complexes of the early transition metals. We focused initially... 

Transition metal polyhydride complexes attracted our attention for their easiness to liberate H2 giving coordinatively unsaturated species under mild conditions.3 The resulting intermediates are highly reactive and interact with various substrates to produce new complexes. In many cases, polyhydride complexes are fluxional, where the hydrogen atoms in the coordination sphere rapidly exchange their positions. 

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