Organic Mercury Compound

any of the compounds containing a carbon-mercury (C—Hg) bond. The two major types of known organic mercury compounds are R—Hg—R’ and R—HgX, where R and R’ are organic radicals and X is an acid group. The two types are interconvertible:

Symmetrizing agents include NH₃, KI, amalgams, and Na₂S₂0₃. The lower homologs of organic mercury compounds of the R₂Hg type are volatile, heavy liquids, while the higher homologs and RHgX are crystalline substances insoluble in water and soluble in organic solvents.

There are four chief methods for obtaining organic mercury compounds. The first involves the reaction of mercury salts with organic compounds of magnesium and lithium:

The second is the substitution of mercury for hydrogen in organic compounds (mercuration):

The third is the addition of mercury salts to unsaturated compounds:

The fourth method involves the decomposition of diazonium salts in the presence of mercury salts (Nesmeianov reaction).

The C—Hg bond in organic mercury compounds is broken by halogens, acids, salts of certain metals, and such oxidizing agents as oxygen and ozone. Upon irradiation, organic mercury compounds decompose with the release of metallic mercury and free radicals; the radicals then undergo further transformations.

Organic mercury compounds are used in organic synthesis and find limited use as fungicides. They are intermediates in certain processes of industrial importance catalyzed by mercury salts, for example, in the synthesis of acetaldehyde by the hydration of acetylene (Kucherov reaction).