Silver trifluoride

The existence of diamagnetic salts of AgF was first reported in 1957 (26), butHttle was known about their properties. In 1988 (27) it was claimed that AgF3 was prepared by a reaction of Ag metal and O2F2 iu CIF. Silver trifluoride [91899-63-7], AgF, has since been prepared (28) from anhydrous HF solutions of AgF 4 salts by addition of BF, PF, or AsF. ... 

The red precipitates of AgF are diamagnetic and isostmctural with AuF. Silver trifluoride is a powerful oxidizing agent and thermodynamically unstable. 

Silver Trifluoride Preparation, Crystal Structure, Some Properties, and Comparison with Aup3 ... 

Silicon Alkali carbonates, calcium, chlorine, cobalt(II) fluoride, manganese trifluoride, oxidants, silver fluoride, sodium-potassium alloy... 

Silver Tetrafluoroborate. Silver tetrafluoroborate [14104-20-2], AgBF, is formed from silver borate and sodium borofluoride or bromine trifluoride. It is soluble in organic solvents. 

PhenyI-3,3-dichIoro-l-azetine (222) forms a 2 1 complex with silver tetrafluoroborate and 1 1 complexes with silver trifluoromethanesulfonate and with boron trifluoride. The dibromo analogue of (222) affords a similar 2 1 complex with silver tetrafluoroborate (79CB3914). 

The monothioacetal is also stable to 12 N hydrochloric acid in acetone (used to remove an TV-triphenylmethyl group) and to hydrazine hydrate in refluxing ethanol (used to cleave an A -phthaloyl group). It is cleaved by boron trifluoride etherate in acetic acid, silver nitrate in ethanol, and tiifluoroacetic acid. The monothioacetal is oxidized to a disulfide by thiocyanogen, (SCN)2- ... 

Rj, R2 = O) by treatment with silver perchlorate in aqueous acetone or boron trifluoride etherate in formic acid at 0°. 

Up to 20 products with different numbers of fluorine atoms and double bonds have been isolated from the fluonnation of benzene with silver difluoride [d], manganese trifluoride [7], potassium tetrafluoroargentate [d], and potassium hexafluoronickelate [24] The composition of the products depends on the fluorinating agents and on the temperature (Table 1)... 

Table 1. Comparison of Fluorination of Benzene with Manganese Trifluoride [7], Potassium Hexafluoronickelate [24], Silver Difluoride [6], and Potassium Tetrafluorocobaltate [6]...

On the other hand, oxidizing fluonnating agents like silver difluoride, xenon difluoride, or bromine trifluoride replace one chlorine group and then cleave the sulfur-nitrogen bond [56],... 

Compound (1) phosphorylates phosphate monoesters and alcohols, although with the latter a considerable excess of alcohol is necessary to obtain satisfactory yields. In the absence of mercuric ions the milder phosphorylating species (3) can be isolated which converts monoalkyl phosphates to pyrophosphate diesters in good yield but does not react appreciably with alcohols unless catalytic amounts of boron trifluoride are added. Amine salts of (3) are converted to phosphoramidates on heating. In the presence of silver ions, O-esters of thiophosphoric acid behave as phosphorylating agents and a very mild and convenient procedure suitable for preparing labile unsymmetrical pyrophosphate diesters, such as the... 

The interaction between nitromethane, the etherate of boron trifluoride and silver oxide gives rise to an extremely dangerous reaction. However, it is difficult to interpret it. Can it be explained by the unstable property of silver tetrafluoroborate or the destabilising effect of boron trifluoride on nitromethane ... 

Olah, G. A. et al., J. Inorg. Nucl. Chem., 1960, 14, 295-296 Experimental directions must be followed exactly to prevent violent spontaneous explosions during preparation of the salt from silver oxide and boron trifluoride etherate in nitromethane, according to the earlier method [1], The later method [3] is generally safer than that in [2],... 

Boron trifluoride etherate, Nitromethane See Silver tetrafluoroborate... 

Iodoform Iodomethane Iron disulfide Isothiourea Ketones Lactonitrile Lead Acetone, lithium, mercury(II) oxide, mercury(I) chloride, silver nitrate Silver chlorite, sodium Water, powdered pyrites Acrylaldehyde, hydrogen peroxide, nitric acid Aldehydes, nitric acid, perchloric acid Oxidizing materials Ammonium nitrate, chlorine trifluoride, hydrogen peroxide, sodium azide and carbide, zirconium, oxidants... 

Methyl cc-D-glucofuranosidurono-6,3-lactone (26) may be obtained exclusively by reaction of 4 with trimethyl orthoformate in the presence of boron trifluoride etherate.28 Its 2,5-dimethyl ether (27) is formed by methyl iodide-silver oxide methylation29,30 (Purdie-Ir-... 

The value of methylation studies in structural determination of carbohydrates is well known. Methylation of sucrose has generally been achieved by the use of dimethyl sulfate-sodium hydroxide,34,35 methyl iodide-silver oxide-acetone,20 sodium hydride-methyl io-dide-N,N-dimethylformamide,35 or diazomethane-boron trifluoride etherate.36,37 The last method (already applied to monosaccharides38,39) has been found particularly useful for sucrose, because it proceeds without concomitant migration of acyl groups. The reaction of 2,3,6,T,3, 4, 6 -hepta-0-acetylsucrose (21) and 2,3,4,6,1, 3, 4 -hepta-O-acetylsucrose (22) with diazomethane in dichloromethane in the presence of a catalytic proportion of boron trifluoride etherate for 0.5 h at —5° gave the corresponding 4-methyl (23) and 6 -methyl (24)... 

The reactivity of acylzirconocene chlorides towards carbon electrophiles is very low, and no reaction takes place with aldehydes at ambient temperature. In the reaction described in Scheme 5.12, addition of a silver salt gave the expected product, albeit in low yield (22—34%). The yield was improved to 79% by the use of a stoichiometric amount of boron trifluoride etherate (BF3OEt2) (1 equivalent with respect to the acylzirconocene chloride) at 0 °C. Other Lewis acids, such as chlorotitanium derivatives, zinc chloride, aluminum trichloride, etc., are less efficient. Neither ketones nor acid chlorides react with acylzirconocene chlorides. In Table 5.1, BF3 OEt2-mediated reactions of acylzirconocene chlorides with aldehydes in CH2C12 are listed. 

Despite these restrictions, the acceptor-bound succinoyl MPEG28 was found to permit glycosylations with glycosyl trichloroacetimidates promoted by boron trifluoride, triflic anhydride, and trimethylsilyl or triethylsilyl triflates, with glycosyl halogenates promoted by silver triflate, and with thioglycosides promoted by the iodonium ion. It is compatible with long-term ester protection, with allylic,... 

It is incorrect to vacuum-plate the internal side of the membrane with silver or gold in the fluoride ISE containing the lanthanum trifluoride membrane [177]. 

The group of ion-selective electrodes with fixed ion-exchange sites includes systems with various membrane structures. The membranes are either homogeneous (single crystals, pressed pellets, sintered materials) or heterogeneous, set in an inactive skeleton of various polymeric materials. Important electrode materials include silver halides, silver and divalent metal chalcogenides, lanthanum trifluoride and various glassy materials. Here, the latter will be surveyed only briefly, for the sake of completeness. 

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