Sulfur nitride ligands

In most of the nonmetaHurgical uses of molybdenum compounds the metal is coordinated by oxygen or sulfur ligands. Molybdenum nitrides, carbides, and sihcides are, however, coming under increasing study for various appHcations. Roughly 75% of all molybdenum compounds are used as catalysts in the petroleum and chemicals industries. 

A related process has been reported for the synthesis of osmium nitrido complexes with 1,2-benzenedithiolate ligands. Thus, the synthesis of 173 was effected by treatment of (Bu4N)[OsNC14] with deprotonated 1,2-benzenedithiol (Eq. (70)). Interestingly, when 173 is treated with Me3OBF4 alkylation is observed to occur on the sulfur this contrasts the reaction of 173 with Ph3CPF6, for which reaction at the terminal nitride is observed [93]. 

The nitride (433), nitrosyl (884), and thionitrosyl (442) have all been crystallographically characterized. Each displays a pentagonal bipyramidal coordination sphere, the nitrogen occupying an axial site. This leads to an elongation of the molybdenum-sulfur vector trans to nitrogen as a result of the trans-influence of the ligands, such that N > NS > NO [trans Mo-S NO 2.561(2), NS 2.608(1), N 2.852(3) A] (Table IV). 

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