Organometallic Chalcogen Complexes

In a preliminary report, the structures of four complexes of the type 

3 Complexes containing Bonds between IVfoin- oap and Transition Metals 

The compound (Et4N)[Br8Cos(CO)gIn] contains complex anions (11) in which the co-ordination about the indium and cobalt atoms is respectively tetrahedral and trigonal bipyramidal. The mean In-Br and In-Co distances are 2.575 and 2.652 A the Br-In-Br and Co-In-Co angles are respectively 

8 and 123.5°. An axial site at each cobalt atom is occupied by the indium atom. The In-Co-C(equatorial) angles range from 75 to 89°. 

The structures of two ruthenocene-mercury halide complexes have been reported at an early stage of refinement (2 0.22), The complex [(ii-C5H5)2Ru]HgBr2 is dimeric (15) with distorted tetrahedral co-ordination 

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In addition to halogen-bridged dimers illustrated above, chalcogen-bridged dimers are another major category of organometallic metal-metal bonded dimers. For example, the complexes shown in equation (23) have been prepared and studied by several groups. 

REACTIONS OF CHALCOGEN ATOM DONORS AND SMALL CHALCOQEN UNITS WITH ORGANOMETALLIC COMPLEXES... 

A discussion of reactions of mono- and polychalcogen organometallic complexes as well as conversions of a number of thiol-containing organometallic compounds is presented in this section. A synthetic method developed independently by Herrmann et al. (282) and Herberhold et al. (283) enabled the synthesis of thio-, seleno-, and telluroformaldehyde complexes 510 and 511, by the addition of methylene to metal-bonded chalcogens (509) (Table V). 

Here we present the advances made in the area of chalcogen-centered derivatives. Sulfur is the element which has been studied in more detail but it is worth mentioning that the species [0(AuPR3)3]+ has found the greatest synthetic applicability, not only in other element-centered complexes but in many organometallic derivatives. We will study each element separately. 

In addition to the synthetic approaches described above, a number of alternative routes to polynuclear metal chalcogenide or chalcogenolate complexes have been described. Organometallic complexes will reduce elemental chalcogen, often resulting in the formation of clusters (e.g., Equation (22)). Many other approaches involve the use of chalcogen reagents other than those described in the previous sections. A selection of these is summarized in Equations (22)-(25) below ... 

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