Mercurous fluoride

Mercuric fluoride [7783-39-3], HgF2, is used in the following conversions where X = Br, I (4,12) ... 

Mercurous fluoride [13967-25 ] Hg2p2, is less effective than Hgp2. The addition of chlorine or iodine to the reagent increases its reactivity owing to the formation of a complex between Hgp2 and HgX2 (4,12). 

Alkyl fluorides have been prepared by reaction between elementary fluorine and the paraffins, by the addition of hydrogen fluoride to olefins, by the reaction of alkyl halides with mercurous fluoride, with mercuric fluoride, with silver fluoride, or with potassium fluoride under pressure. The procedure used is based on that of Hoffmann involving interaction at atmospheric pressure of anhydrous potassium fluoride with an alkyl halide in the presence of ethylene glycol as a solvent for the inorganic fluoride a small amount of olefin accompanies the alkyl fluoride produced and is readily removed by treatment with bromine-potassium bromide solution. Methods for the preparation of alkyl monofluorides have been reviewed. ... 

Diphenylthioalkanes react with mercuric fluoride to give 1-fluoro-l-phenylthio-alkanes. Provide a detailed description of a likely mechanism for this reaction. Consider such questions as (1) Is an SnI or an Sn2 process most likely to be involved (2) Would NaF cause the same reaction to occur (3) Why is only one of the phenylthio groups replaced ... 

An alternative route to the reaction of mercuric fluoride with fluoroolefins in liquid hydrogen fluoride [154] was developed during the early and middle 1970s This improved method involved the reaction of fluoroolefins and mercury salts in the presence of alkali metal fluorides m aprotic solvents [i5J, 156] (equation 118)... 

Waterfeld, A. et al., J. Chem. Soc., Chem. Comm., 1982, 839 Reaction of chlorine fluoride with trifluorosulfur nitride is rather hazardous and may lead to violent explosions. A safer alternative preparation is to use chlorine and mercuric fluoride in place of chlorine fluoride. 

In this work on compounds containing the C—F link, it was obviously desirable to prepare 2-fluoroethanol, both for toxicity tests on the compound itself, and as a starting material for the production of other fluorine compounds. Swarts1 was unable to obtain 2-fluoroethanol by the action of silver fluoride or mercuric fluoride on either ethylene chlorohydrin or ethylene bromohydrin. He obtained acetaldehyde in each case. He ultimately obtained fluoroethanol in very poor yield by the indirect method of hydrolysing fluoroacetin (from bromoacetin and mercuric fluoride) for 80 hr. with dilute mineral acid. 

The reaction of a perfluoromercurial with sulfur is particularly well suited to synthesis of hexafluorothioacetone. The first step is addition of mercuric fluoride to hexafluoropropylene in liquid HF which gives bis(hexafluoroiso-propyl)mercury. 

Several mercurous salts absorb ammonia in the dry state or react with ammonia in aqueous solution. The products formed have been described from time to time as ammino-mercurous compounds. It appears, however, that these supposed mercuro-ammines are nonexistent, and that the substances produced by the action of ammonia are really mercuric derivatives mixed with mercury. For instance, mercurous fluoride in the dry state is blackened by ammonia gas, forming a compound HgF(NH3). This substance gives off ammonia at 100° C. and is black in colour the colour is now regarded as being due to finely divided mercury, and the compound as a derivative of mercuric fluoride and not of mercurous fluoride. Numerous instances of the same kind may be quoted. For example, mercurous chloride with aqueous ammonia yields a black compound this again has been proved to be a mixture of finely divided mercury and mercuric chloroamidc. The reaction may be represented thus ... 

Organic compounds Organic fluorine compounds arc made by reaction of the corresponding alkane chloro-compounds with silver fluoride, mercurous fluoride, antimony trifluoride, titanium tetrafluoridc. and the arene fluoro-compounds by the diazo-reaction using hydrogen fluoride, and otherwise. The effect of the continued replacemenl of hydrogen atoms by fluorine atoms is an initial increase in reactivity, followed by a reversal of this effect, so lhal the highly substituted compounds arc relatively inert, See also Fluorocarbon. 

Dimethylmercury, CH3—Hg—CH3, is a volatile compound of bp 96°, whereas mercuric fluoride F—Hg—F is a high-melting solid having mp 570°. Explain what differences in bonding in the two substances are expected that can account for the great differences in physical properties. 

Protonation of mercuric fluoride results in formation of highly electrophilic cation 3 (Eq. 5), which is able to attack the C=C bond of HFP at 85°C to give the corresponding mercurial [6] ... 

Fluoroolefins add mercuric fluoride at 50- 100 °C to give bis(polyfluoroalkyl)-mercury derivatives. Reaction is usually carried out in hydrogen fluoride as a solvent. This process was reviewed and the electrophilic nature of this process established [6]. Addition to olefin starts by the attack of cation 3 (Eq. 5) on the double bond of fluoroolefin. 

Potassium. Mixtures of mercuric bromide, mercuric chloride, mercuric fluoride, mercuric iodide, or mercurous chloride with potassium explode on impact.11... 

Silver fluoride is difficult to prepare in anhydrous form, and it has the further disadvantage that only half of its fluorine is available because the exchange reaction stops with the formation of the compound AgF AgCl. Mercuric fluoride and mercurous fluoride are, therefore, more convenient reagents despite the lower fluorine content of mercurous fluoride. 

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