Cluster compounds main group

Current concepts in modem chemistry/Transition metal cluster chemistry/Main group-transition metal mixed clusters/Cluster compounds of main group elements/ Synthetic analogues of the active sites of iron-sulfur proteins... 

Derivatives of the boranes include not only simple substituted compounds in which H has been replaced by halogen, OH, alkyl or aryl groups, etc., but also the much more diverse and numerous class of compounds in which one or more B atom in the cluster is replaced by another main-group element such as C, P or S, or by a wide range of metal atoms or coordinated metal groups. These will be considered in later sections. 

Supplement to Mellor s Comprehensive Treatise on Inorganic and Theoretical Chemistry , Vol. V, Boron Part A, Boron-Oxygen Compounds , Longman, London, 1980, 825 pp. See also J. R. Bowser and T. P. Fehlner, Chap. 1 in H. W. Roesky (ed.). Rings, Clusters and Polymers of Main Group and Transition Elements, Elsevier, Amsterdam, 1989, pp. 1-48. 

The Wade rules can be applied to ligand-free cluster compounds of main-group elements. If we postulate one lone electron pair pointing outwards on each of the n atoms, then g — 2n electrons remain for the polyhedron skeleton (g = total number of valence elec-... 

R. J. Gillespie, Ring, cage, and cluster compounds of the main group elements. Chem. Soc. Rev. 1979, 315. 

Salter, I. D. Molecular Compounds of Gold with Main Group and Transition Metals. Metal Clusters in Chemistry, Vol. 1, Braunstein, P. Oro, L. A. Raithby, R. R. Wiley-VCH Weinheim 1999, pp 509-534. 

The first two groups are distinguished by the fact that autoclave syntheses are used mainly by the Soviet (or Russian) cluster school [1,2,11,16-22], while the American and other schools do not use autoclave techniques [1,23-35]. This distinction is historical and applies not only to technetium compounds, but also to other cluster compounds of d-transition elements [36-41]. Cotton et al. [28] did use an autoclave method once, but it was not further developed [1]. 

Whitmire, Kenton H., Main Group-Transition Metal Cluster Compounds of the... 

Metal Preferences. LVC s are formed mainly by transition metals to the right in the periodic table (especially elements in Group 8). This is in part due to the availability of d electrons that can be used in back-donation to the 7r-accepting ligands. Moreover, the formation of LVC s is not particularly "row-sensitive" by which I mean that the first-transition-series metals, Fe, Co and Ni, tend to form most of the same cluster compounds as their congeners, Ru, Rh, Pd and Os, Ir, Pt. 

Despite its unsaturated nature, benzene with its sweet aroma, isolated by Michael Faraday in 1825 [1], demonstrates low chemical reactivity. This feature gave rise to the entire class of unsaturated organic substances called aromatic compounds. Thus, the aromaticity and low reactivity were connected from the very beginning. The aromaticity and reactivity in organic chemistry is thoroughly reviewed in the book by Matito et al. [2]. The concepts of aromaticity and antiaromaticity have been recendy extended into main group and transition metal clusters [3-10], The current chapter will discuss relationship among aromaticity, stability, and reactivity in clusters. 

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