Hydrogen fluoride, liquid oxidants

Nitrosyl chloride [55], nitrosyl fluoride-hydrogen fluoride liquid complexes (NOF3HF, NOF 6HF) [56], nitrous acid-hydrogen fluoride solutions [57, 5 ] nitrogen trioxide (prepared in situ from nitric oxide and oxygen) [59] and rert-butyl nitrite-hydrogen fluoride-pyndine [60] have been substituted for sodium nitrite in the diazotization step... 

Chlorine dioxide Copper Fluorine Hydrazine Hydrocarbons (benzene, butane, propane, gasoline, turpentine, etc) Hydrocyanic acid Hydrofluoric acid, anhydrous (hydrogen fluoride) Hydrogen peroxide Ammonia, methane, phosphine or hydrogen sulphide Acetylene, hydrogen peroxide Isolate from everything Hydrogen peroxide, nitric acid, or any other oxidant Fluorine, chlorine, bromine, chromic acid, peroxide Nitric acid, alkalis Ammonia, aqueous or anhydrous Copper, chromium, iron, most metals or their salts, any flammable liquid, combustible materials, aniline, nitromethane... 

Arsenic trioxide and calcium oxide incandesce in contact with liquid hydrogen fluoride. 

The new method of Yoneda s group132 is also a one-pot diazotization-fluoro-de-diazoniation in a liquid-liquid two-phase mixture of pyridine and hydrogen fluoride. Yields for 25 aromatic amines and diamines are 50-100%, except for 2-and 3-fluorobenzoic acid, the three nitroanilines, 3- and 4-diaminobenzene and 4,4 -diaminodiphenyl-oxide (10-50%). In their 1994 paper the authors demonstrate that, in the same system, the photochemical decomposition gives in many cases significantly higher yields than the thermal reaction. The most spectacular increase in yield was found for the fluorination of 2-fluoroaniline where o-difluorobenzene was obtained photochemically in 80.2% yield, but thermally only in 0.6% ... 

The tables contain nearly all of the n.m.r. information currently available in the literature. Although there are more fluorinated monosaccharides known, for many of them no n.m.r. data have been reported so far. Throughout the Tables, S stands for solvent A for hexadeuterioacetone, B for hexadeuteriobenzene, C for deuteriochloro-form, D for deuterium oxide, F for liquid hydrogen fluoride, H for water, M for tetradeuteriomethanol, N for dichlorodideuteriomethane, and s for hexadeuteriodimethyl sulfoxide. 

Hydrofluoric acid like water is an associated liquid, and even the gas, as we shall soon see, is associated. It has the power of uniting with fluorides. It also seems to be an ionizing solvent for a soln. of potassium fluoride in liquid hydrogen fluoride is an excellent conductor it also possesses marked solvent powers. According to E. C. Franklin,7 the liquid readily dissolves potassium fluoride, ehloride, and sulphate sodium fluoride, bromide, nitrate, chlorate, and bromate acetamide and urea. The solvent action is not so marked with barium fluoride, cupric chloride, and silver cyanide while calcium and lead fluorides copper sulphate and nitrate ferric chloride, mercuric oxide, and magnesium metal, are virtually insoluble in this menstruum. Glass also is not affected by the liquid if moisture be absent. The liquid scarcely acts on most of the metals or non-metals at ordinary temp., though it does act on the alkali metals at ordinary temp., much the same as does water, with the simultaneous production of flame. 

The oxidative fluorination of C-H bonds of the side chain in toluene l43 and ethylbenzene derivatives 4 has been reported.45 4fi These alkyl aromatics bearing electronegative substituents are cleanly fluorinated on the alkyl group in liquid hydrogen fluoride in the presence of lead(IV) oxide,45 nickel(IV) oxide,45 silver(II) fluoride,46 cobalt(III) fluoride,46 or cobalt(III) acetate.46... 

Thionyl fluoride has also been obtained in excellent yield by the interaction of liquid hydrogen fluoride and nitrogen sulphide in the presence of a little copper oxide, the reaction being best effected in a copper bomb at 100° C. The gas, which issues on opening the bomb, can be collected in a receiver cooled by liquid air.1... 

Polyacrylamides are chemically stable towards acids (TFA, hydrogen fluoride [163]), bases, and weak oxidants or reducing agents. Problems, which might be related to cleavage of the amide bonds in poly(7V,/V-dialkylacrylamidcs), were encountered upon treatment of such supports with sodium in liquid ammonia [169]. 

Aluminum trifluoride is in most widespread use as a catalyst for the disproportionation of chlorofluorocarbons. The preparation of an active aluminum trifluoride catalyst is dependent on the initial compound (aluminum trichloride or aluminum oxide), the hydrogen fluoride or chlorofluorocarbon activation component, and the reaction phase (gas or liquid).10... 

FLUORINE. CAS 7782-41-4], Chemical element symbol F. at. no. 9. at. wt. 18.9984, periodic table group 17 (halogens), mp -2l9,62nC, bp - 188.1°C. density 1.696 g/l (gas at 0CC, 1.108 g/cm (liquid at bp). Fluorine is a pale yellow gas, poisonous, very reaclive. combines with most other elements in the dark, except it does not combine readily with oxygen. Critical pressure is 55 atm critical temperature is -129.2 C. First identified by Scheele in 1771. but not isolated until 1886 by Moissan who electrolyzed fused potassium hydrogen fluoride in a platinum apparatus. Fluorine is a high-tonnage chemical, used mainly in the production of fluorides, in the synthesis of fluorocarbons, and us rut oxidizer for rocket fuel. 

Electrochemical fluorination 168,169> is a commercial process for perfluorina-tion of aliphatic compounds. The reaction is performed in liquid hydrogen fluoride -potassium fluoride at a nickel anode. The mechanism is not known free fluorine cannot be detected during electrolysis, so it seems probable that fluorination is a direct electrochemical reaction. Theoretically, hydrogen fluoride-potassium fluoride should be a very oxidation-resistant SSE, and it might well be that the mechanism is analogous to that proposed for anodic acetamidation of aliphatic compounds in acetonitrile-tetrabutylammonium hexafluorophosphate 44 K... 

It is known that dry powders, such as sodium bicarbonate, calcium chloride, magnesium oxide, and calcium hydroxide, readily react with hydrogen fluoride. Use of similar materials for the control of liquid spills was discussed in Chapter 3 of this guideline. 

Hydrofluoric acid — (HF) A solution of hydrogen fluoride in water. The pure hydrogen fluoride is characterized by Mw of 20.0063 gmol-1 m.p. -83.55 °C (1 atm) b.p. 19.5 °C (latm). When concentrated, this colorless fuming liquid is extremely corrosive and can dissolve almost all inorganic oxides such as silicate compounds or oxides of metals like stainless steel, aluminum, and uranium however, it can be stored in casted iron bottles because a corrosion-resistant iron fluoride layer protects the metal. It is used for several purposes such as the preparation of titanium oxide nano tube arrays [i], silicon nanoparticles [ii] and electrochemical etching of silicon [iii], electrochemical deposition of lithium [iv], etc. 

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