Alkylmercury salts

Radicals can also be synthesized by the reduction of alkylmercury salts. For example, in the presence of sodium borohydride, compound 5-2 reacts to form the radical, 5-3. 

Despite their toxicity, alkylmercury salts have been used widely in research due to their versatility as synthetic intermediates. 

Hex-5-enyl-l-mercuric bromide (III) is reduced to 1-hexene (IV) by sodium amalgam, whereas sodium borohydride, lithium aluminum hydride, and tri-77-butyltin hydride gave a mixture of IV and methylcyclopentane. This is taken as evidence that sodium amalgam reduction of alkylmercury salts does not proceed via a free radical pathway [72]. 

The kinetics of the reaction of hexamethylditin with Hg(II) chloride or alkylmercury salts are second order. Trialkylstannylmercurials RjSnHgCl or R3SnHgR are potential... 

Pd(II) salts promote the carbonylation of organomercury compounds. Reaction of phenylmercury chloride and PdCl2 under CO pressure affords benzophenone (429)[387]. Both esters and ketones are obtained by the carbonylation of furylmercury(II) chloride in alcohol[388]. Although the yields are not satisfactory, esters are obtained by the carbonylation of aryl- and alkylmercury(II) chlorides[389,390]. One-pot catalytic carbonylation of thiophene, furan, and pyrrole (430) takes place at the 2-position via mercuration and transmetallation by the use of PdCl2, Hg(N03), and CuCl2[391]. 

With Alkenes. The interaction of an Hg salt with an alkene in the presence of a nucleophile can lead to the formation of a 8-substituted alkylmercurial ... 

Elemental mercury is mainly hazardous as vapor. There is less danger of absorbing the metal for the digestive tract. Like the alkylmercurials, elemental Hg affects the central nervons system, accompanied with such symptoms as tremors, irritability, and sleeplessness. Kidney damage is also reported due to influence of inorganic mercury salts due to a complexation of mercury by the protein metallothionein, which accumulates in the renal tubules. 

Mercuric salts of carboxylic acids decompose in uv light or in the presence of peroxides to form alkylmercury derivatives. Aqueous peroxydisulfate can be used to decarboxylate N-acetylamino acids to give aldehydes or ketones, acetamide, and CO2. ... 

The addition of nucleophiles to alkenes is mediated hy Hg(II) salts and catalyzed hy Pd(II) salts. The difference between the two reactions is the fate of the alkylmetal(II) intermediate obtained after addition of the nucleophile to the rr complex. The alkylmercury(II) intermediate is stable and isolable, whereas the alkylpalladium(Il) intermediate undergoes rapid /3-hydride elimination. 

Of the organomercurials, the short-chain alkylmercury(ll) compounds form salts with the halogens, which are highly volatile, while hydroxides, nitrates, and in particular dicyan-diamides, are less volatile. The short-chain alkylmercurials are highly soluble in organic solvents and lipids. Further, they easily bind mainly to sulfhydryl groups, and thus mainly exist in protein-bound form in biological material. 

R can be alkyl or aryl and R has usually been aryl 212, 214), though more recently the dimethyl compounds (CH3)2AsMgX (X = Br, I) have been prepared 194, 204). Trialkyl- and triarylarsines react with alkylmercury halides affording salts containing ions such as [CH3HgAs(C2Hs)3] 288a). 

For small-scale hydrations, it is convenient to use mercury salts, such as mercuric acetate, Hg(OAc)2, to carry out the addition of H—OH across a double bond. This process is called oxymercuration. In this two-step process, an alkene is first treated with mercuric acetate, then the initial alkylmercury compound formed is reduced with sodium borohydride (Na BH4). 

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