Transition Metal Tellurolates

Complexes with tellurocarbonyl ligands such as telluroureas can be formulated as tellurolate complexes. 

An X-ray structural analysis of pentacarbonyl (A,A diethyl-A,A -dimethylenetelluro-urea)chromium indicated that the tellurolate form is preferred in the solid state. However, these complexes are described on page 520. 

Bromomagnesium arenetellurolates reacted with bis[cyclopentadienyl]dichlorotitanium or -zirconium to yield products with the arenetellurolates replacing the chloride ligands  

Bis[n-cyclopentadienyl]bis[benzenete11uroIato]zirconium(IV) A solution of phenyl lithium is prepared from 1.88 g (12 mmol) of bromobenzene and 0.20 g (29 mmol) of lithium in 40 ml of anhydrous diethyl ether. Under nitrogen, 1.53 g (12 mmol) of tellurium powder are added, and the mixture is stirred for 6 h. Then, a suspension of 1.46 g (5.0 mmol) of bis[7t-cyclopentadienyl]dichlorozirconium in 30 ml of benzene is added and the mixture is stirred for 2 h. The solvent is removed under reduced pressure and the residue is recrystallized from benzene/hexane yield 2.4 g (77%). 

Bis[7t-cyclopentadienyl]bis[benzenetellurolato]titanium(IV) reacted with bis[tricarbonyl-(nitrosyl)iron] mercury to produce a Ti — Te dinuclear complex bridged by benzenetelluro-lato groups.  

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The aim of this chapter is to review the chemistry of chalcogenolates in the last 10 years. The more recent reviews in this field included chalcogenolates of the s-block elements,13,14 early transition metal thiolates,15 metal complexes with selenolate and tellurolate ligands,16 copper(I), lithium and magnesium thiolates,17 functionalized thiolate complexes,18 19 pentafluorobenzenethiolate platinum group compounds,20 tellurium derivatives,21 luminescent gold compounds,22 and complexes with lanthanide or actinide.23... 

Tellurolates replace chloride in transition metal halo complexes, in copper(I) chloride and in mercury(II) chloride. 

The oxidative addition of chalcogen-chalcogen bonds in RE—ER is widely applied in transition metal chemistry and is often a useful route for the preparation of thiolates, selenolates and, to a more limited extent, tellurolates. The oxidative addition of X2 = HO—OH and PhC(0)0—0C(0)Ph is also known and, in the case of Ptu complexes, gives predominantly trans products 47... 

It has long been known that thiolate ligands (RS ), which are formally derived from thiols (RSH) by deprotonation, are well suited to form metal complexes (1). Specific reviews of this area have covered the structural chemistry of metal thiolates (la), the coordination chemistry of metal thiolates from a bioinorganic perspective (lb), transition metal thiolates (lc), and, most recently, early transition metal thiolates (Id). Because of potential thione-thiol tautomerism, a review dealing with complexes of heterocylic thione donors (le) is also relevant. This chapter concentrates on thiolate complexes of copper , lithium, and magnesium, but we also mention, for comparison or contrast, many related species of silver and gold and of some complexes that contain selenolate and tellurolate ligands. However, it should be emphasized that we have not attempted a comprehensive literature search outside the primary field of interest. 

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