Organomercury compounds organolithium

Metathesis reactions continue to be extensively employed in the synthesis of organomercury compounds. While most reactions involve the use of organolithium or Grignard reagents, other organometallic compounds are sometimes used as starting materials. 

There are several useful means for preparation of organomercury compounds. The general metal-metal exchange reaction between mercury(II) salts and organolithium or magnesium compounds is applicable. The oxymercuration reaction discussed in Section... 

Organolithium compounds, 2 69 ring stacking, 37 82-92 systems capable of, 37 82-83 uncomplexed, structure, 37 53-54 X-ray crystal structure, 37 48 Organomagnesium halides, 2 71 Organomercury compounds, see Mercury, -carbon compounds Organometallic complexes... 

An alternative method for preparing metallocenyllithium derivatives, convertible into organosilicon compounds, is based on cleavage of organomercury compounds with organolithium reagents. It was used for the silylation of ferrocene (113, 151) ... 

Another approach for the preparation of either symmetrical or unsymmetrical iodonium salts used organolithium or organomercury compounds and (dichloroiodo)arenes [12]. The problem of the formation of unwanted isomers during reactions involving aromatic electrophilic substitution may also be overcome by the condensation of iodosylarenes with iodylarenes [12]. Several iodonium triflates were prepared in high yield from activated or mildly deactivated arenes with iodosylbenzene and triflic anhydride or triflic acid [13,14] or sulphur trioxide [15]. Some of these compounds are shown in Table 8.2. 

Group 2B elements Cd and Hg—organozinc and organomercury compounds. Group 3B elements B, Al, Ga, In and T1—organoboron, organoaluminium and, organolithium compounds. 

A different method of preparation is advisable if the pure, solvent-free organolithium compound is required. In a procedure due to Schlenk and Holtz50 the organolithium compound is prepared from metallic lithium and the organomercury compound in an indifferent solvent since most organolithium compounds, in particular the higher alkyl derivatives, are very readily soluble in hydrocarbons, they can be easily separated from the separating mercury and then obtained pure by evaporation of the solution. 

Grignard reagents are also synthesized by addition reactions of alkynes, addition reactions of unsaturated compounds having C=S groups, reactions of cycloalkanes, reactions with organolithium compounds or organomercury compounds, etc. [4,15,27,28],... 

As shown in eqs. (5.3)-(5.7), organozinc compounds are easily prepared by the reactions of zinc compounds or zinc metal with organometallic compounds such as Grignard reagents, organoaluminum compounds, organomercury compounds and organolithium compounds [12,13,18]. 

R. C. Larock, Organomercury Compounds in Organic Synthesis, Springer-Verlag, Berlin, 1985. B. J. Wakefield, The Chemistry of Organolithium Compounds, Pergamon, Oxford, 1974 B. J. Wakefield, Organolithium Methods, Academic Press, Orlando, Florida, 1988. 

The synthesis of alkyl(aryl)chlorosilanes, based on the use of metalorganic compounds, can be carried out with the help of organomercury, organoz-inc, organosodium, organolithium, organoaluminum and organomagne-sium compounds. 

A general method for the synthesis of organomercurials is the transmetallation of mercury (II) salts with other organometallic species. Organolithium and -magnesium compounds continue to be widely employed for the preparation of complexes with formula RHgX or HgR2 (see equation 1). 

A variety of organolithiums, including benzylic, vinylic, alkynic, and 1-alkoxylithium compounds, are also accessible through the lithium-tellurium exchange, which involves the treatment of diorganotellurides with w-BuLi at —78 °C in THF (eq 25) 222 vinyllithium derivatives have been prepared from the corresponding organomercurials by essentially the same... 

In this section, we will discuss organometallics in which the metal is cadmium, mercury, or zinc. Grignard reagents and organolithium compounds can be converted to heavy-metal derivatives by reaction with salts of these metals. The reaction is driven forward by the tendency for formation of the ionic salt of the more electropositive metal. This reaction is well documented for organocadmium compounds and organomercurials ... 

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