Organometallic chemistry clusters

As a result of the systematic application of coordination-chemistry principles, dozens of previously unsuspected stnicture types have been synthesized in which polyhedral boranes or their anions can be considered to act as ligands which donate electron density to metal centres, thereby forming novel metallaboranc elusters, ". Some 40 metals have been found to act as acceptors in this way (see also p. 178). The ideas have been particularly helpful m emphasizing the close interconnection between several previously separated branches of chemistry, notably boron hydride clu.ster chemistry, metallaboranc and metallacarbaborane chemistry (pp. 189-95). organometallic chemistry and metal-metal cluster chemistry. All are now seen to be parts of a coherent whole. 

Slovokhotov, Yu.L. and Struchkov, Yu.T (1984) X-ray crystal structure of a distorted tetrahedral cluster in the salt [(Ph P)4Au4N] BF4 . Geometrical indication of stable electronic configurations in post-transition metal complexes and the magic number 18-e in centred gold clusters. Journal of Organometallic Chemistry, 177, 143-146. 

This exemplifies a quite general reaction in organometallic chemistry, the cluster-opening conversion of an w-hapto ligand into an ( — 1 )-hapto ligand by addition of a nucleophile X . The converse, cluster-closing conversion accompanies removal of X . 

Mo, W) are very useful reagents in organometallic chemistry, in particular for the formation of metal-metal bonded complexes. This is illustrated below by the high-yield synthesis of a heterotrinuclear complex having a linear M— Pt—M core, Section C. The trinuclear complexes M—M —M react with tertiary phosphines3,4 to give heterotetranuclear clusters M2M 2( 7-C5H5)2 (CO)6(PR3)2 and details of the synthesis of two of these (M = Mo M = Pd, Pt) are presented in Section D. 

One of them is the reduction of simple metal salts in the presence of CO or similar ligands, the most general starting reaction in organometallic chemistry. The method has been used to prepare all basic metal clusters, and during the last five years improved procedures have been described for Ru3(C0)j2 and Os3(CO)j2 121, 227,... 

A detailed account of the descriptive chemistry of the heavier transition metals is beyond the scope of this book. Many aspects of the chemistry of these elements such as metal-metal multiple bonds, metal clusters, organometallic chemistry, and coordination chemistry are discussed in other chapters. The present discussion will be limited to a comparison of the similarities and differences of the heavier metals and their lighter congeners. 

The application of spectroscopic techniques familiar in organometallic chemistry to the unique features of carbidocarbonyl clusters has become more evident since the previous review of this field (1). Vibrational spectroscopy and 13C NMR have yielded useful data relevant to the geometric and... 

His Editorial activities include a monograph on cluster chemistry, three undergraduate textbooks and many published reviews. He has also edited several books and served on the editorial boards of a number of international journals. He was Regional Editor of the Journal of Organometallic Chemistry from 1996 to 2006 and is Managing Editor of Structure and Bonding. 

---