Bimetallic molybdenum systems

Fe—Fe bond can be assigned structures 201 or 202 based on spectral data. The other product of this reaction is 193 (R = r-Bu), however, it is produced in minor amounts. Complexes 199 (R = R = r-Bu, R = Ph, R = r-Bu) were obtained. Reaction of 146 (M = Mo, R = Ph, R = R = Ft, R = r" = Me) with (benzyli-deneacetone)iron carbonyl gives rise to the bimetallic complex 200 (M = Mo), which reacts further with the free phosphole to form the bimetallic heteronuclear sandwich 203. The preferable coordination of the molybdenum atom to the dienic system of the second phosphole nucleus is rather unusual. The molybdenum atom is believed to have a greater tendency to coordinate via the trivalent phosphorus atom than via the dienic system. 

When the three-component system described in Section 1.39.5 is subjected to hydrothermal conditions of higher pH (5 to 8) and more extreme temperatures and reaction times, the resultant oxide materials often exhibit architectures in which the secondary metal is directly incorporated into a bimetallic oxide network and/or in which the molybdate cluster identity is lost upon fusing into one- or two-dimensional molybdenum oxide substructures. 

Supported bimetallic systems containing molybdenum and a modifier such as Co, Ni... are frequently encountered in the literature, especially as desulfurisation catalysts. On the other hand, little attention has been devoted to Pd-Mo/oxide systems so far, despite their use for the CO + NO reaction by Halasz et al. [1] and several mentions as selective hydrogenation catalysts in the patent literature. 

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