Molybdenum compounds with

R. Davis, L. A. P. Kane-Maguire in Molybdenum Compounds with r2 - >/fJ Ligands in Comprehensive Organometallic Chemistry, G. Wilkinson, F. G. A. Stone, W. Abel, Eds., Vol. 3, p 1149fF., Pergamon, Oxford 1982. 

Compounds 4-7 (Table 1) belong to this group. The physicochemical properties of the given binuclear clusters are close to those of the analogous rhenium and molybdenum compounds with the quadruple M-M bonds and are as a rule isostructural with them [1,89,90]. 

These complexes are generally prepared by methods similar to those employed for the dinitrosyl compounds, treatment of a low-valent molybdenum compound with NO or a nitrosyl derivative being the principal method. Compounds and major physical properties are collected in Table 3. 

Current emphasis in hydrodesulfurization of fuels has generated considerable interest in the reactions of molybdenum compounds with hydrogen sulfide or mixtures of H2S/H2. The following section will outline some of the pertinent reactions of molybdenum compounds with hydrogen sulfide or mixtures of H2S/H2. Details of the chemistry of hydrodesulfurization catalysts containing molybdenum are referenced later in this report. 

The molybdenum compound with the empirical formula MoClg does not possess the simple Mo + ion its structure is [MogClg]4Cl4, the complex cation being cubic, with chlorine atoms at the eight corners and molybdenum atoms at the six face centres (Fig. 244). Tungsten forms a similar compound but, unlike the Mo complex which is stable in aqua regia, it is easily oxidised. 

Analysis of the Bonding in Dinuclear Molybdenum Compounds with Bridging Methyl and Hydride Ligands as a Representative Study... 

Table 4 Comparison of calculated bond orders for a series of dinuclear molybdenum compounds with those predicted by two alternative electron-counting methods. In each case, the bond order predicted by the [p.-LX] half-arrow method corresponds exactly to that derived by consideration of the orbital occupations, whereas the half-electron method fails for compounds with bridging hydride and methyl ligands. Data ttiken from reference 6...

Both oae-step and two-step oxidation processes are known. A number of catalyst systems are known most use a molybdenum compound as the main component. The acryhc acid is esterified with alcohol to the desired acryhc ester ia a separate process (63—66). 

Molybdenum Oxide. Molybdenum compounds incorporated into flexible PVC not only increase flame resistance, but also decrease smoke evolution. In Table 10 the effect of molybdenum oxide on the oxygen index of a flexible PVC containing 50 parts of a plasticizer is compared with antimony oxide. Antimony oxide is the superior synergist for flame retardancy but has Httle or no effect on smoke evolution. However, combinations of molybdenum oxide and antimony oxide may be used to reduce the total inorganic flame-retardant additive package, and obtain improved flame resistance and reduced smoke. 

Lake or pigment dyes form insoluble compounds with aluminum, barium, or chromium on molybdenum salts the precipitates are ground to form pigments used in paint and inks. 

In the second step, methacrolein is oxidized to methacrylic acid at a relatively lower temperature range of 250-350°C. A molybdenum-supported compound with specific promoters catalyzes the oxidation. 

Allylic acetates give dienes when heated with certain palladium or molybdenum compounds. 

Li Q, Walter EC, van der Veer WE, Murray BJ, Newberg JT, Bohannan EW, Switzer JA, Hemminger JC, Penner RM (2005) Molybdenum disulfide nanowires and nanoribbons by electrochemical/chemical synthesis. J Phys Chem B 109 3169-3182 Tenne R, Homyonfer M, Feldman Y (1998) Nanoparticles of layered compounds with hollow cage structures (inorganic fuUerene-like structures). Chem Mater 10 3225-3238 Shibahara T (1993) Syntheses of sulphur-bridged molybdenum and tungsten coordination compounds. Coord Chem Rev 123 73-147... 

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