Organomercury

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Organomercury refers to the group of organometallic compounds containing mercury.

Important organomercury compounds are the methylmercury cations, CH₃Hg⁺; ethylmercury cations, C₂H₅Hg⁺; dimethylmercury, (CH₃)₂Hg and thiomersal, C₉H₉HgNaO₂S.

Organomercury compounds, and dimethylmercury in particular, are notoriously toxic and find use as antifungal agents and insecticides. They are stable to air and moisture and some are sensitive to light.

Contents 1 Synthesis 2 Reactions 3 External links 4 See also 5 References

[edit] Synthesis

General methods for the synthesis of simple diorganomercuries have similarities to that of organocadmium compounds.

A general synthetic method to diethylmercury is the reaction of mercury chloride with two equivalents of the Grignard reagent, ethylmagnesium bromide, in diethyl ether.^[1] Et₂Hg is a liquid with density 2.466, and boiling point 57°C at 16 torr. The compound is slightly soluble in ethanol and soluble in ether.

Diphenylmercury is prepared by reaction of mercury chloride and phenylmagnesium bromide.

The naphthalene derivative, di-2-naphthylmercury, can be prepared from the corresponding diazonium salt, β-naphthalenediazonium chloride, and copper metal.^[2]

A method for the synthesis of phenyl(trichloromethyl)mercury starts from phenylmercuric chloride and sodium trichloroacetate.^[3] This compound on heating generates dichlorocarbene.

[edit] Reactions

Due to its toxicity and low nucleophilicity compared to organocadmium and organozinc compounds in group 12 organomercury compounds have limited use. A mercury-carbon bond is present in one of the intermediates in the oxymercuration reaction of alkenes to alcohols with mercuric acetate. A related reaction forming phenols is the Wolfenstein-Boters reaction.

[edit] External links

• Listing of relevant organomercury pesticides Link
• Listing of relevant organomercury pesticides Link

[edit] See also

• Other chemistries of carbon with other group 12 elements: organozinc compounds, organocadmium compounds and organomercury compounds.

[edit] References

1. ^ Synthetic Methods of Organometallic and Inorganic Chemistry Vol 5, Copper, Silver, Gold, Zinc, Cadmium, and Mercury W.A. Herrmann Ed. ISBN 3-13-103061-5
2. ^ Organic Syntheses, Coll. Vol. 2, p.381 (1943); Vol. 12, p.46 (1932) Article.
3. ^ Organic Syntheses, Coll. Vol. 5, p.969 (1973); Vol. 46, p.98 (1966). Article