Mercury-carbon single bond

A useful aspect of the mercury(II) hydride method is that it can be directly coupled with the many standard techniques for heteromercuration of alkenes and cyclopropanes. The resulting overall transformation adds a heteroatom and a carbon atom across the carbon-carbon double bond of an alkene or the carbon-carbon single bond of a cyclopropane. This is a difficult transformation to conduct by standard ionic techniques. An alkene thus becomes an equivalent of synthon (12) and a cyclopropane of synthon (13 Scheme 34). Many equivalent transformations (like haloetherification and phenylselenolactoniza-tion) are available to make precursors for tin hydride mediated additions. 

Carbon-carbon single bonds may be cleaved when the two carbon atoms bear substituents that sufficiently stabilize the anions formed on the uptake of electrons to make them relatively weak bases. The reduction of ethanetetracarboxylate esters illustrates that these esters are reducible at rather negative potentials in DMFf-10% water at a mercury cathode at 60-65°C with splitting of the central carbon-carbon bond [3] ... 

Bond, A.M., Czerwinski, W.A. and Llorente, M. (1998) Comparison of direct current, derivative direct current, pulse and square wave voltammetry at single disc, assembly and composite carbon electrodes stripping voltammetry at thin film mercury microelectrodes with field-based instrumentation. Analyst, 123, 1333-1337. 

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