Pentafluorophenyl derivatives mercury

Pentafluorophenyllithium in ether reacts slowly with mercury at 15° C to afford bis(pentafluorophenyl)mercury, a compound recently prepared by another route (Section VII, B). The lithium reagent has very recently been used to prepare pentafluorophenyl derivatives of boron (79a), tin 19b), lead 19b), and several transition metals 19c). 

Unsymmetrical phenylpentafluorophenyl and methylpentafluorophenyl compounds are obtained from the appropriate mercury(ll) halide [45], or by decarboxylation procedures [69], and these mixed derivatives are particularly susceptible to attack. Nevertheless, bis(pentafluorophenyl)mercury is very resistant to acid cleavage for example, it can be recrystallised from concentrated sulphuric acid, but the well-known ligand-exchange process, e.g. with mercury(ll) chloride, occurs very rapidly and presumably by a four-centre process [45] (Figure 10.23). 

Bis(pentafluorophenyl) ytterbium is prepared similarly by transmetallation from ytterbium metal and bis(pentafluorophenyl) mercury (Deacon and Vince, 1976 Deacon et al., 1977, 1979). The complex (CgFjjjYb (THF)4 is characterized by infrared, ultraviolet, and F NMR spectra. Evidence is presented for green (CgFjjjEu (Deacon et al., 1979), and less stable derivatives (CgHF4)2Yb with the... 

The preparation of tris(pentafluorophenyl)-silyI, -germyl, and -stannyl derivatives of cadmium and mercury has been described. Thus tris(penta-fluorophenyl)silane yields bis[tris(pentailuorophenyl)silyI]cadmium by the route ... 

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