Clusters selenolates

Ni and Se is observed in the structure of the mixed selenide/selenolate cluster [Ni2oSei2(SeMe)io] (7, Figure 13.5) [29]. The cluster contains a Ni2oSei2 core that is stabilized by surface Me groups bonded to Se centers. The interstitial selenide ligands (Se ) arise from Se-C bond scission reactions of the MeSe reagent. 

Metal thiolate complexes will reduce elemental sulfur or red selenium via the oxidative elimination of RSSR. In a similar manner, metal selenolate complexes ean be used to reduce elemental selenium. The resulting E ligands favor the formation of polynuclear cluster complexes, due to the greater tendency of E (vs. RE ) to form bridging interactions between metal centers. Originally developed in the synthesis of [Fe4Se4(SPh)4], this method has been well utilized in the synthesis of a number of iron thiolate/sulfide clusters, as well as their selenide counterparts (Equation (5)). More recently, sulfur- and selenium-containing lanthanide clusters (see Section 7.2.5.5) have been synthesized by the displacement of ER from Ln(ER)3 ... 

The approach of using RE-TMS reagents is readily adaptable to introduce specific chemical functionality in R, and has thus been extended to the synthesis of ternary CuHg E nanoclusters via the use of silylated copperchalcogenolate complexes, [(L)3Cu(E-TMS)] (E = S, Se, Te L = PPr", PEts) (Figure 3) as soluble delivery agents of CuE (Equation (IQ). Silylated ferro-cenyl-selenolate reagents have also been used to introduce redox-active ferrocene units onto copper selenium cluster cores (Equation (17)) ... 

Figure 34 Ball-and-stick representation of the cluster core of [Cu8 Fe(7j -C5H4Se)2 4(PPh2Et)4] (51), demonstrating the surface ferrocenyl selenolate ligands.

In analogy to compounds linked to the carbon atoms of the cluster through a spacer, B-substituted phosphonates bearing the ort/to-carborane cluster in the ester moiety were also reported. These compounds were prepared from o-carborane-9-thiol or -selenol. The phosphonates can be prepared either by reaction with methylchlorophosphonates or by Michaelis-Arbuzov reaction of phosphonothioites or -selenoites (Scheme 2.6). 

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