Molybdenum solid-state synthesis

Nitrogenase is another big target of cluster synthesis. The X-ray elucidation of the active center of the Fe-Mo cofactor and P-cluster (5) has accelerated the efforts to find rational preparative methods of trinuclear or cubane-type clusters containing molybdenum (6-9). The raft cores in these cluster complexes are one of the general structural units also in solid-state compounds, and the mutual relationships are very important. A number of review articles are now available on the syntheses, structures, and other properties of metal chalcogenide cluster compounds (6, 7,10-24). 

Chromium, Molybdenum and Tungsten The intramolecular rotational behaviour of a series of highly substituted Ti -arene chromium and molybdenum compounds has been examined in detail. Dynamic processes in the solid state, using spin-lattice relaxation time measurements, have been studied for two structurally characterised polymethyl benzenechromium tricarbonyl complexes. The mechanism of migration of the Cr(CO)3 unit from the six to the five membered ring in indenyl anions has been reported. The synthesis and cyclic voltammetry of (Ti -phenylmethylsila-14-crown-5)chromiumtricarbonyl has appeared. ... 

Due, R, Gonthier, S., Brunelli, M., et al. (2006). Hydrothermal Synthesis and Structure Determination of the New Vanadium Molybdenum Mixed Oxide VI. lMoO.905 from Synchrotron X-Ray Powder Diffraction Data, J. Solid State Chem., 179, pp. 3591-3598. 

Tris(2,4-pentanedionato)molybdenum(III) is a dark purple crystalline solid, m.p. 228 to 230°. It reacts rapidly with atmospheric oxygen to form a diamagnetic brown product, m.p. 284 to 285° (decomp.), containing pentaposi-tive molybdenum. This oxidation state is determined by dissolution in concentrated hydrochloric acid to produce a solution which has the same absorption spectrum in the visible region as green oxopentachloromolybdate(V), by cerimetric titration of this concentrated hydrochloric acid solution after chloroform extraction of the liberated 2,4-pen-tanedione, and by independent synthesis from a brown... 

The closed-shell nature of aluminosilicates renders them ineffective for certain reactions favoured by transition (d-block) elements. Haushalter has made efforts to prepare stable shape-selective microporous solids involving molybdenum phosphates [15]. These solids are prepared hydrothermally in aqueous HjPO in the presence of cationic templates along with anionic octahedral-tetrahedral frameworks containing Mo in oxidation state less than 5+ and possessing Mo-Mo bonds. Some of these contain around 40 vol% accessible internal void space. There is rich chemistry in these systems and there is considerable potential for applications. Based on this approach one may indeed discover novel microporous and catalytic oxide systems. Several open-framework metal phosphates [16] and carboxylates [17] with different connectivities have been prepared by hydrothermal synthesis. 

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