Molybdenum carbonyls structure

A structural study of a molybdenum carbonyl complex of phosphabenzene has shown that the phosphorus is a-bonded to the... 

Aside from the structure obtained for 1-chloroborepin referred to in Section 14.20.3.3, no other X-ray studies of simple borepins or benzoborepins have been reported however, an X-ray structure for molybdenum carbonyl complex 12 has been obtained <19970M1884> and was compared to previously reported structures for 13 and 14 <1992AGE1255> shown in Figure 3. 

Treatment of molybdenum carbonyl with fluorine diluted in nitrogen at —75°C gives a product of composition Mo2F9. The structure of this substance has not been... 

Molybdenum Carbonyl Catalysts. The elucidation of the structure and activity of molybdenum carbonyl catalyst systems, the first catalysts reported active for metathesis, continues to be the subject of investigation. Brenner and BurwelE " have identified the dominant surface species formed during the interaction of Mo(CO)6 with 7-alumina at various temperatures. Sub-carbonyl species, Mo(CO)y ads Cy = 3,4, 5, or 6), are formed in the reversible decomposition of Mo(CO)e at temperatures below 100° Activation at 100° C of Mo(CO)6 on partially hydroxylated alumina forms... 

All three members of the electron transfer chain [Mo(CO)2(S2C2Me2)]" (n = 0,1, 2) were isolated and characterized. The complexes have trigonal prismatic geometries, and structural, spectral, and electrochemical properties that are consistent with the redox orbital having predominantly sulfur-ligand based character (>80%) behavior consistent also with DFT calculations. Closely related benzene- and 2,4-di-i-butyl-benzene-dithiolene complexes, [Mo(LL )(bdt)2] (L = 0, L = PPha, L = L = PMeR2 (R = Me or Ph)) were obtained by thioether S-dealkylation of appropriate dttd (22) complexes of molybdenum carbonyls and oxo species. 

The reactivity of molybdenum carbonyls in reaction with Lewis acids is comparable to the reactivity of tungsten carbonyls. The treatment of a nitrile carbonyl compound with an equimolar amount of tetrachlorotin in dichloromethane gives the oxidative-addition product, a mononuclear seven-coordinate compound [MoCl(SnCl3)(CO)3(NCMe)2], in good yield [36, 40]. The same compound was isolated from the reaction of a binuclear compound and acetonitrile. The crystal structure of the reaction product is similar to that... 

With 3-chloroperbenzoic aci4 the dominant reaction is the formation of oxirane structures, which can react further. Metal carbonyls, e.g. Fe3(CO)i2, react only with cisoid units. Otherwise the metal atoms combine with two different units of the polyacetylene or isomerization occurs, resulting in cis configurations. All these types of reaction have been confirmed by IR spectroscopy. CO insertion can also be observed with molybdenum carbonyls. Cyclo-addition of maleic anhydride (MA) and 3,4-dichloromaleic anhydride (DCMA) leads to adducts like that shown below. The adduct formed by DCMA is worth mentioning because it give rise to fusible polyacetylene (165-80°C) [15]. 

What formulas would you expect for the metal carbonyls of (a) molybdenum, (b) osmium (c) rhenium Note that the simple carbonyls shown in Figure 23-15 have one metal atom per molecule. Some metal carbonyls are hinuclear that is, they have two metal atoms bonded together in the carbonyl structure. Also, (d) explain why iron and nickel carbonyls are liquids at room temperature, whereas that of cobalt is a solid, and (e) describe the probable nature of the bonding in the compound Na[V(CO)g]. 

All three structures have 0(, symmetry and are very similar. The bond length from the central atom to the carbonyl group is slightly different in each compound, and it is longest for the molybdenum substituent. The internal structure of the carbonyl groups is essentially unchanged by substitution. ... 

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