Bromide clusters

Of special interest is the dehydration of polynuclear technetium bromide clusters, which contain hydroxonium cations with different numbers of hydration water molecules. Analysis of the results obtained leads us to conclude that at 140-200 °C dehydration occurs with a partial decomposition of the [H30(H20)3] + cations (30). 

The nucleophilicity of the organocuprate cluster derives mainly from the filled copper 3d orbital, in combination with the carbon orbital associated with bonding to copper. These orbitals for the TS for reaction with methyl bromide and ethylene oxide are shown in Figure 8.4. 

X-ray diffraction, which showed that the structure of the [Tc2Cl8]2 ions is analogous to that of the isoelectronic cluster rhenium and molybdenum chlorides and bromides with a quadruple M-M bond [1,89,90] (Fig. la, Table 1). 

Figure 5 shows a scheme for synthesizing all the bromides of polynuclear technetium clusters presently known. Table 2 summarizes details of their ap-... 

Table 2. Appearances and main properties of polynuclear bromide technetium clusters [11, 44, 53, 72, 76]...

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