Mercury fluorides as fluorinating

Silver(I) Fluoride. Silver(I) fluoride, like the mercury fluorides, has been used as a fluorinating agent for many years. It can be used in most of the reactions for which other inorganic fluorides are used. Its use has declined in recent years, primarily because it is deliquescent, light-sensitive, and easily reduced. Only one-half of its fluorine is available for fluorination because it forms the compound AgCl-AgF, which has very little fluorinating power. 

The principal constituents of the paniculate matter are lead/zinc and iron oxides, but oxides of metals such as arsenic, antimony, cadmium, copper, and mercury are also present, along with metallic sulfates. Dust from raw materials handling contains metals, mainly in sulfidic form, although chlorides, fluorides, and metals in other chemical forms may be present. Off-gases contain fine dust panicles and volatile impurities such as arsenic, fluorine, and mercury. 

Inorganic chemicals and fertilizers include acids (e.g., sulfuric, nitric) and alkalies (e.g., caustic soda, soda ash), chlorine, ammonia, and ammonia-derived fertilizers. They also include fluorine derivatives (e.g., hydrogen fluoride), phosphates, potash, pigments (e.g., titanium dioxide), and certain metals such as mercury. 

F2N.C( NF).NF.C(NF2)2F mw 265.04, N 26.42%, FB +7.2% FB is analogous with OB, being applied hereafter to fluorinated compds wherein the F is not already on C it is calculated in the same manner, the factor 1900/mw being used instead of 1600/mw) liq, bp ca 80° mp below —130° a 50/50 mixt of the cis and trans isomers, Prepd by fluorinating biguanide sulfate with nitrogen diluted fluorine and a sodium-magnesium fluoride mixt at 0° Proposed as an oxidizer for propints. Should be treated with extreme caution. May readily detonate into CF4 and N2. Do not let vapors contact mercury Refs 1) Beil, not found 2) J.J. Hockstra,... 

Attempts to manufacture anhydrous mercury(II) fluoride by methods more conventional than the action of elemental fluorine upon mercury(II) chloride (vide supra) showed that aqueous reagents invariably yielded a dihydratc salt which could not be converted into anhydrous mer-cury(II) fluoride, because it always eliminated hydrogen fluoride in preference to water. In an effort to circumvent this, mercury(II) fluoride generated in situ has been used as the reagent for the substitution of one or several halogens by fluorine in various types of compounds (see Houben-Weyl, Vol. 5/3, p202 for pre-1959 reports). 

Many metal fluorides beside KF have been tried as nucleophilic fluorinating agents but only a few succeeded in establishing themselves as such. We will briefly survey here fluorides of silver, mercury, cesium and antimony. 

The first step in the two-step synthesis of l,l-difluoro-1-phcnylethane (4) is the hydro-fluorination of phenylacetylene with hydrogen fluoride cither in diethyl ether at 0 C (18% yield) or at 150 C in the gas phase with 13-14% mercury(II) oxide on activated carbon as catalyst to give the vinyl monomer... 

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