Reactivity studies, transition metal group 12

In the 20 years since 1982, there has been, of course, an avalanche of activity in the coordination chemistry of the early transition metals, Groups 3-6. This has been driven by further fundamental study but also by strategic work in reactivity and catalysis (including biological chemistry) and in solid state and thin film technologies. 

The aim of this report is to show what advantages can be provided by variable temperature IR speetroseopy and our approach to study the reactivity of transition metal and main group element hydrides. We focus on the Vmh bands and their response to hydrogen bonding and proton transfer, but will also mention behaviour of other bands such as Vqh, vco etc. These... 

While all the preceding examples dealt with reactions of closed shell TM compounds, chemical processes in which the TM is not coordinatively saturated are of great importance in assessing the intrinsic binding properties and the reactivity of transition metals (and/or their ions), without the influence of ligating groups, counter-ions, or solvent molecules. Experimentally, a wealth of data on the reactivity of such systems has been accumulated over the past few years by means of mass spectrometric studies. Since open shell situations are more difficult to describe than electronically saturated situations, only a few mechanistic studies employing approximate... 

The chemistry of transition metal-carbyne complexes is rather less developed than the chemistry of carbene complexes. This is almost certainly because reactions which form new carbyne complexes are relatively rare when compared with those forming metal carbenes. The few theoretical studies of carbyne complexes which are available indicate that close parallels exist between the bonding in carbene and carbyne compounds. These parallels also extend to chemical reactivity, and studies of Group 8 complexes again prove instructive. 

M H (M = Si, Ge, Sn) bonds are reactive to undergo oxidative addition of transition metals, homolytic cleavage giving group 14 metal radicals, and so on. Some studies have been reported on the formation of M E (M = Si, Ge, Sn E = S, Se, Te) bonds by using the group 14 metal hydrides. 

The aqua ion is not easily reduced nor oxidized. It is the slowest reacting of the bivalent transition metal ions with e " k = 7.7 X 10 M s ) and the product Mn+q is very reactive. However Mn(CNR)5 (R = a variety of alkyl and aryl groups) is stable and the selfexchange in the Mn(l,ll) hexakis(isocyanide) system has been studied by Mn and H nmr line broadening. The effects of solvent, temperature, pressure and ligand have been thoroughly explored. 

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