Triosmium Complexes

Aime S, Diana E, Gobetto R, Milanesio M, Vails E, Viterbo D (2002) Structural and spectroscopic study of the dihydrogen bond in an imine triosmium complex. Organometallics 21 50-57... 

Studies of a number of polymetallic complexes also provided evidence for C—H coordination. Particularly notable was a beautiful NMR study by Calvert and Shapley of a triosmium complex, which was shown to exist as an equilibrium mixture of two structures, one of which included a C—H—Os linkage.,JJ... 

In organometallic clusters, ligands frequently appear to move over the surface uf the metal framework. The triosmium complex. Os,(CO)10(mj-tj -CH3CH2C C-CH2CHj), in Fig. 15.54 provides an example in which the alkyne moves over the... 

Over the past few years there has been a growing body of literature on the photophysics and photochemistry of organometallic Os complexes. A significant portion of the literature has focused on the photochemistry and transient photophysical characterization of triosmium clusters involving Os - Os bond homolysis. There is also a significant body of literature on CO loss from diosmium and triosmium complexes. 

Ultraviolet photolysis of the diphosphine complex [Os3(CO)io(bpcd)] (bpcd, Struct. 3) yields an orthometalated hydrido triosmium complex as the exclusive product (Fig. 17). The mechanism presumably involves initial CO loss with subsequent coordination of one phenyl of the diphenylphosphino unit followed by the insertion process [100]. 

Acetonitrile derivatives of [0 3(CX>),2] have been used extensively in the preparation of new triosmium complexes. Thus, [Os3(CO) (McCN)l reacts with (Cp3)2P-N=PPh, and 3,3-... 

The triosmium complex Os3(CO)9(/i-H)(jU3- j -Ci2H6) is accessible from the reaction between acenaphthylene and Os3(CO)io(NCMe)2. Further treatment with acenaphthylene at 160 °C leads to identification of four products, including two dinuclear species, 525 and 526, both of which share structural similarities with 523. A further analogous example is 527 (R = C=CFc), obtained from the reaction between (FcC Z )2 and Os3(CO)io(NGMe)2. ... 

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