Heteronuclear group 11 clusters

Various homo- or heteronuclear cluster species which contain both a- and 7r-bonded alkynyl groups have been synthesized and characterized, e.g., [Ag5(C=CPh)6]-,278... 

Pignolet, L. H. Krogstad, D. A. The Heteronuclear Cluster Chemistry of the Group 11 Metals—Some Recent Advances. In Gold, Progress in Chemistry, Biochemistry and Technology Schmidbaur, H., Ed. Wiley Chichester, U.K., 1999, pp 429-493. 

The square face of cluster 5 is readily capped by a number of different metal fragments affording octahedral heteronuclear clusters in high yield. The dianion 5 reacts with the Group 6 complexes M(CO)3L3 (M = Cr,... 

Addition of Co2(CO)8 to the //2-vinylidene complex (40) (Section IV,A,6) affords the heteronuclear cluster derivative (88) in 55% yield, in which the vinylidene group now bridges all four metal atoms ... 

The Group IB metal site preferences in heteronuclear cluster compound allow coinage metal exchange reactions between clusters and mononuclear complexes to be used as a high yield synthetic route to novel trimetallic species containing two different Group IB metals. These reactions are discussed in detail in Section II,D,2. 

Although the vast majority of Group IB metal heteronuclear clusters have been synthesized using one of the generally applicable rational preparative procedures outlined in Sections II,A,1 and II,A,2, a number of such species have been obtained via routes for which the nature of the product cannot be predicted in advance or via procedures which have not been widely used. These other methods of synthesis are outlined in this section. 

A number of Group IB metal heteronuclear clusters undergo reactions involving the loss of a CO ligand (e.g., 25,26,51,55,57,58,100), and Eq. (61) shows an example (58). In some cases, the reaction is known to be... 

In some cases, clusters containing M(PR3) units undergo reactions involving the cleavage of M—P bonds to produce other Group IB metal heteronuclear clusters (e.g., 170,171). Equation (64) shows an example (170). 

Protonation and deprotonation reactions have been reported for Group IB metal heteronuclear clusters (e.g.,66,103), but cleavage of the coinage metal moiety from the cluster often occurs instead (e.g., 20). 

Group IB metal heteronuclear clusters undergo a variety of interesting dynamic processes in solution, and these are surveyed in this section. Only processes which are rapid on the NMR time scale and which can, therefore, be observed by NMR spectroscopy have been included. 

HETERONUCLEAR CLUSTERS IN WHICH NO LIGANDS ARE ATTACHED TO THE GROUP IB METALS... 

Most heteronuclear clusters in which no ligands are attached to the Group IB metals were prepared using one of the few generally applicable rational methods that are currently available for the synthesis of these species. These preparative routes all involve the addition of Ag+, either to preformed cluster anions (98,118,123,190,192) or to neutral polynuclear (188) or dimeric (189,191) compounds. Equations (66) and (67) show examples (189,190). 

Heteronuclear Clusters in Which No Ligands Are Attached to the Group IB Metals... 

Although the vast majority of Group IB metal heteronuclear clusters have simple two-electron donor ligands attached to the coinage metals, a small number of species with other types of ligand bonded to the Group IB metals have also been reported. Examples are listed in Table XIX. 

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