Dimeric sulfido

Rhenium(III) complexes with sulfur dioxide ligands have been obtained by oxidation of dimeric sulfido-bridged complexes either by air or by NO(PFe). The oxidation of the bridging sulfur atoms is facilitated by the high electron density at these ligands. 

In addition to thiolate-bridged dimers, sulfido complexes containing metal-metal bonds show related chemistry. Of particular interest are the products of reaction between [(C5R5)(CO)3Mo]2 and sulfur (equation 24). In complexes such as these, the ability to assign bond orders is no longer simple. The intemuclear distances are supportive of metal-metal bonds for a majority of the complexes, but the exact bond orders are uncertain in some cases. 

No other bis(sulfido-bridged) or bis(thiolato-bridged) dimeric Fe4S4 clusters have been produced. The linear [Fe4S6(SEt)4]4 cluster can be described... 

Figure 5 Diagrammatic representation of the monocysteinate bridged cluster [ Fe4S4(L) 2(p-Cys-OMe)]3 where H3L is l,4,7-tris(4-sulfanylbenzoyl)-l,4,7-triaza-cyclononane [33], with a depiction of the bis(sulfido-bridged) dimeric Fe4S4 cluster [ Fe4S4(SPh)2 2(p-S)2]4- [34],...

Alkyne adducts of M0CI4 were reported in 1973 by Greco et al. (221). An array of monomeric (222) and dimeric (223) d2 W(IV) complexes related to [W(C1C=CC1)C15] has been reported by Dehnicke. Schrock has prepared Mo(IV) and W(IV) alkyne derivatives with halide, alkoxide (224), and thiolate (225) ligands present. Other d2 monomers with alkyne ligands have terminal oxo (226,227), nitrene (228), and sulfido (61) ligands. 

The deprotonation reaction of Cp2Ti(SH)2 with NaH in THF proceeds unexpectedly with the elimination of GpH to give the anionic sulfide-bridged titanium(iv) dimer, Na2[CpTi(/x-S)(S)]2. The molecular structure of this compound has been determined by X-ray diffraction and shows a terminal sulfido ligand with a short Ti-S bond distance of ca. 2.2 A, indicating nearly double bond character (Scheme 417). It adopts a yy/z-Ti=S configuration and is stabilized by interactions with THF-solvated sodium cations.1009... 

---