Dialkyl mercury compounds

Occupational mercury exposures generally occur when workers inhale metallic mercury vapors. Some dermal absorption may occur from skin contact with contaminated air, but the rate is low (less than 3% of the inhaled dose). Dialkyl mercury compounds, which are not normally found in hazardous waste sites, are rapidly and extensively absorbed from both dermal and inhalation routes of exposure. 

Diethyl ditellurium and bis[triethylgermyl] mercury yielded ethyl triethylgermyl tellurium3. Triorgano tin hydrides cleave the Te — Te bond in diaryl and dialkyl ditellurium compounds forming the organo triorganostannyl tellurium as one of the products (p. 191). 

Both halves of a diaryl ditellurium molecule are transformed into aryl alkyl tellurium compounds in reactions with dialkyl mercury compounds1 2. Diphenyl mercury did not react1. 

Organolithium solutions are pyrophoric and should be handled with caution. Dialkyl-mercury(II) compounds are toxic furthermore, the lower members are volatile. 

The principal utility of dialkyl- and diaryl-mercury compounds, and a very valuable one, is in the preparation of other organo compounds by interchange, e.g.,... 

A generally applicable method of preparing dialkyl- and diaryl-mercury compounds is by treatment of alkyl or aryl halides or alkyl sulfates with sodium amalgam 160... 

Unsymmetrical diaryl-, dialkyl-, and alkyl(aryl)-mercury compounds are conveniently prepared by reaction of organomercuric halides with the necessary Grignard reagent 170... 

Other elements which react satisfactorily with dialkyl and diaryl mercury compounds include the alkali metals, the alkaline earths, Al, Ga, Sn, Pb, Sb, Bi, Se and Te (see Chapters 3, 4). In some cases the formation of a metal amalgam assists the reaction. The transition elements, when they react, give metallic mercury and a mixture of hydrocarbons. An unstable organotransition metal species may be formed initially, only to decompose. The reactions,... 

DIALKYL AND ARYL MERCURY COMPOUNDS AND ALKYL AND ARYL MERCURY HALIDES... 

Beryllium dialkyls (BeR2, R = Me, Et, Pr", Pr, Bu etc.) can be made by reacting lithium alkyls or Grignard reagents with BeCl2 in ethereal solution, but the products are difficult to free from ether and, when pure compounds rather than solutions are required, a better route is by heating Be metal with the appropriate mercury dialkyl ... 

The most extensively investigated 1,2-diazocines are 3,4,5,6,7,8-hexahydro derivatives, of interest in connection with studies on the properties of cyclic azo compounds. These compounds are obtained from the hydrazines (159) usually not isolated, by oxidation with yellow mercury(II) oxide. 3,8-Diaryloctahydrodiazocines are prepared by reduction of the azines dialkyl and unsubstituted derivatives are obtained by hydrolysis of the N,N-bis(ethoxycarbonyl) compounds (69JA3226,70JA4922). Cyclization of 2,7-diaminooctane with IFs gave the 3,3,8,8-tetramethyl compound (78CB596). 

The photooxidation of mercury alkyls is difficult to elucidate in that complicating reactions of mercury and the alkyl compounds themselves tend to obscure the simple oxidation of alkyl radicals. Martin and Noyes00 found that with mercury dimethyl they did not find formaldehyde to be a principal product of the photooxidation above 100°C. The reason is not obvious, but probably reflects the unsatisfactory nature of mercury dialkyls for studying the oxidation of alkyl radicals. 

Complexes of the following elements with dialkyl and/or diaryl telluriums have been prepared B, Ga, Sn, V, Ta, Cr, Mo, Mn, Re, Fe, Ru, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Cd, and Hg. Examples of coordination compounds with diorgano telluriums as ligands are given in Table 14 (p. 489). The adducts of mercury(II) halides with diorgano telluriums were used in ihe older literature to separate diorgano telluriums from reaction mixtures (Vol. IX, p. 1057). 

Whereas Al alkyls and alkyl halides are completely hydrolyzed in water, dialkyl compounds of Ga, In, and Tl give well-characterized compounds in aqueous solution. Thallium gives very stable ionic derivatives of the type R2T1X (X = halide, SO4-, CN , NO3, etc.) which resemble the isoelectronic mercury dialkyls R2Hg in being unaffected by air and water. The [TlMe2]+ ion is linear, but does not form an aquo complex like Me2Ga(H20)2. 

Arseno-compounds, heated in sealed tubes with ammonium sulphide, form sesquisulphides, R2AS2S3. Mercury dialkyls react, forming aryl-dialkylarsines ... 

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