Bonding, molybdenum-sulfur double

It seems likely that the active site for dinitrogen binding involves the molybdenum atom. It has been established by EXAFS that the coordination sphere consists of several sulfur atoms at distances of about 235 pm. An Mo=0 double bond, so common in complexes of Mo(IV) and Mo(Vl), is not present. There are other heavy atoms, perhaps iron, nearby (—270 pm). The ultimate source of reductive capacity is pyruvate, and the electrons are transferred via ferredoxin (see page 911) to nitro-... 

A theoretical study of desulfurization of thiirene and methyl thiirene on the molybdenum catalysts MoS3H3 and M0S4H4 was reported to involve hydrogenation of the double bond in the first step <2003BCSE75>. The extended Huckel technique was used to determine the orientation of thiirene adsorbed on vacant sites of MoS3H3. The molecule is adsorbed preferentially in the vertical sense through the sulfur atom <2000JSOA127>. 

While all of the transformations detailed above take place at low-valent metal centers, a double sulfur-carbon bond cleavage process has also been postulated to occur at the molybdenum(VI) center (527, 528, 839). Thus, thermolysis of organic isocyanates with [Mo02(S2CNR2)2] affords imido-disulfide complexes, [Mo(NR )(S2)(S2CNR2)2] (Fig. 289), in moderate yields. The fate of the aminocarbyne fragment remains unknown and further, since monosulfido... 

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