Reactions with Metal Fluorides

Fluorination of Cgg leads to products with a higher volatility than Cgg itself [37]. Reaching a certain degree of fluorination, which is dependent on the applied 

Another isomer of the fluorofnllerene ether CggFjgO has been found recently [61], This fluoroxyfluoro fuUerene CjoFjyOF is generated by insertion of O into a C-F bond. 

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The best method for the preparation of CF3SF is the reaction of CFgSCl with HgFg in a nickel or platinum apparatus at 130°C, followed by removal of the reaction products by condensation in liquid nitrogen 144). Analogous reactions with metal fluorides lead to other sulfenyl fluorides 102,189) ... 

Thus, COFj is a very powerful fluoride acceptor (for comparisons with other fluoride acceptors, see [1212a]), and this tendency dominates many of its reactions with metal fluorides. 

Other fluorofullerenes are obtained by reaction with metal fluorides. These may be less reactive than elemental fluorine, but consequently enable a much better selectivity in product generation. Depending on the metal chosen (either transition or rare earth metals might be considered), the composition of the fluorine compound ranges from C )F2 to about C60F36. Not only binary, but also ternary metal fluorides can be employed (Table 2.10). 

Reactions With Metals. AH metals react to some extent with the halogen fluorides, although several react only superficiaHy to form an adherent fluoride film of low permeabHity that serves as protection against further reaction. This protective capacity is lost at elevated temperatures, however. Hence, each metal has a temperature above which it continues to react. Mild steel reacts rapidly above 250°C. Copper and nickel lose the abHity to resist reaction above 400 and 750°C, respectively. 

Reactions with Metals. Many common metals react with OF2, but the reaction stops after a passive metal fluoride coating is formed (3,4). 

At 225—275°C, bromination of the vapor yields bromochloromethanes CCl Br, CCl2Br2, and CClBr. Chloroform reacts with aluminum bromide to form bromoform, CHBr. Chloroform cannot be direcdy fluorinated with elementary flourine fluoroform, CHF, is produced from chloroform by reaction with hydrogen fluoride in the presence of a metallic fluoride catalyst (8). It is also a coproduct of monochlorodifluoromethane from the HF—CHCl reaction over antimony chlorofluoride. Iodine gives a characteristic purple solution in chloroform but does not react even at the boiling point. Iodoform, CHI, may be produced from chloroform by reaction with ethyl iodide in the presence of aluminum chloride however, this is not the route normally used for its preparation. 

With nitriles, products from addition of one or two equivalents of halogen fluoride can be obtained [725, 726, 127, 128] (equations 25 and 26) on reaction with chlorine fluoride or bromine and an alkali metal fluoride. 

Swarts reaction org chem The reaction of chlorinated hydrocarbons with metallic fluorides to form chlorofluorohydrocarbons, such as CCI2F2, which is quite inert and nontoxic. svarts re,ak-shan ... 

Fluorofullerenes have been prepared by reaction with halogen fluorides, by direct fluorination with F2 or by fluorination with noble gas fluorides [7,8,14], The reaction with high valence metal fluorides is the most versatile route for the synthesis of CsoFnH. 

Reaction of Halides and Sulfonate Esters with Metal Fluorides... 

Selenium hexafluoride, SeFg, the only clearly defined hexahalide, is formed by reaction of fluorine with molten selenium, It is more reactive than the corresponding sulfur compound, SFs, undergoing slow hydrolysis. Selenium forms tetrahalides with fluorine, chlorine, and bromine, and dihalides with chlorine and bromine. However, other halides can be found in complexes, e.g,. treatment of the pyridine complex of SeF/i in ether solution with HBr yields (py)2SeBrc Selenium tetrafluoride also forms complexes with metal fluorides, giving MSeF complexes with the alkali metals. 

Analysis of the Raman spectra of a variety of hexafluorometallate salts derived from reaction of N02F with metal fluorides, nitrosyl, and nitryl hexafluorometallates, indicates that the [N02]+ cation in the solids formed is linear (60b). 

Thionyl fluoride can be prepared by the reaction of thio-nyl chloride with metal fluorides such as zinc(II) fluoride1 and arsenic (III) fluoride,2 and with metal fluorosulfites.3 It is also obtained by the action of hydrogen fluoride upon a mixture of tetrasulfur tetranitride and copper(II) oxide4 and by the reaction of hydrogen fluoride with thionyl chloride in the absence of6 or in the presence of6 antimony(V) fluoride as catalyst. Another method and the simplest on a laboratory scale involves the reaction of antimony(III) fluoride with thionyl chloride in the presence of antimony ) chloride as catalyst.7 This last procedure is described below. 

The generation of CF2 can also be achieved by hydrolysis of C1CF2H (33). Neither direct conversion of CF3H to CF2, and hence CF2=CF2, nor decomposition of (CF3)3CH to (CF3)2C=CF2, is observed. Addition of HF in the presence of F- to (CF3)2C=CF2, forming (CF3)3CH, takes place under normal reaction conditions (36). Some of the anhydro-fluorides react with metal fluorides (bases in HF) to form saltlike compounds. 

Metal and nonmetal oxides are converted to fluorides or oxyfluorides by reactions with halogen fluorides as illustrated by the following equations ... 

The industrial manufacturing methods of NF3 are classified in three categories electrolysis method, reactions of F2 with liquid phase ammonium-acid fluoride, and reactions of F2 with metal fluoride ammonium complex. 

Due to the relatively forcing reaction conditions, i.e. severe heating in strongly polar media, that are usually applied in potassium fluoride fluorinations. several attempts have been made to find mild and efficient methods to fluorinate with metal fluorides. l-(Mesyloxy)octane is converted into 1-fluorooetane in high yield with aqueous potassium fluoride in the presence of catalytic amounts of tributyldecylphosphonium bromide. Similarly, (m-fluoropropoxy)ni-trobenzenes are obtained in good yield from the corresponding mesylates with potassium fluo-... 

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