Oxidative Fluorination

Xenon difluoride has been used to oxidize a number of antimony compounds [102, 109] in yields ranging from 73 to 98%. Elemental fluorine oxidized tris(pen-tafluorophenyl)stibine to tris(pentafluorophenyl)stibine difluoride in 98% yield [706]. Oxidative fluonnation of stibines has also been accomplished with iodine pentafluoride [707]. 

Stability Stable. Reacts vigorously with fluorine, fluorine oxides, and chlorine in the presence of moisture. Nitric oxide is non-corrosive and may be used with most common structural materials. However, in the presence of moisture and oxygen, corrosive conditions will develop as a result of the formation of nitric and nitrous acids. 

Formed by fluorine oxidation of the dilithium salt of hexafluoroacetone hydrate, it is unstable and explosive. The chloropentafluoro homologue is similar. Proponents of their use as reagents claim that the dimethyl and methyltrifluoromethyl analogues are not explosive this seems improbable, especially since the less stressed lower dioxetanes (homodioxiranes) are all dangerous. 

It has also been recognized that micro-structured components, because of their low mass and thermal inertia, are able to offer short response times for unsteady state periodic operations. Micro-reactors have been used successfully for fluorination, oxidations and both heterogeneous [63-65] and homogeneous hydrogenations [66]. A review on gas-liquid micro-structured reactors has been published [67]. The very small material inventory when using micro devices offers another advantage, notably as a laboratory tool for screening applications, kinetics determination and process data acquisition, where the main concern is... 

Only two stable fluorine oxides are known. Except for an early investigation of the decomposition of F202, studies of decomposition kinetics have been confined to F20. There still remains considerable doubt concerning the mechanisms by which these two compounds decompose to their elements. Unlike its chlorine analogue, FO has defied spectroscopic detection in the fluid phases, although it is considered an important intermediate in many of the reactions of F20. 

F20 FLUORINE OXIDE -24.8186 -1.9007E+02 1.5985E+01 -4.1421E-02 4.8042E... 

Synonyms Fluorine monoxide oxygen fluoride fluorine oxide... 

Fluorine oxide also merits attention. This is a gas liquefiable at — 144.8°C and weakly endothermic. Its heat of formation — AHt=— 9.2 kcal/mole [58],... 

Fluorine oxide, 1 109 Fluoroboric acid, HBF(, 1 25 Fluoropentamminecobalt(III) nitrate, 4 172... 

Figure IV. A. 3. is a heat of combustion plot of the elements with fluorine as the oxidizer. One can carry through the same arguments as those made for the oxygen plot except it is well to remember that many of the metal fluorides are gaseous under the combustion chamber conditions that prevail. Since BF is a gas, the significance of boron compounds as fuels with fluorine oxidizers particularly changes for the better. Comparison of figures IV. A. 1. and IV. A. 3. will show that H2 -02 and H2 - F2 have the same standard state heat release. Yet above it was stated that the specific impulse with hydrogen-fluorine was the greater. This comparison again points out the limitations of the plots, which do not take into account the diss-...

The next oxidizer in the list given previously is F20, fluorine monoxide. F20 which has a density about that F2 has been considered because it is not as corrosive as F2. But the presence of oxygen defeats the purpose of the fluorine oxidizer water forms, dissociates and causes a decrease in the performance. As discussed earlier, with carbon containing fuels the presence of the 0 atom is beneficial. It should be pointed out that there is no advantage of R O over an appropriate molar mixture of F, and 02. which would be appreciably less expensive. 

For laboratory preparations of small quantities of the halogens (except fluorine), oxidation of acidic solutions containing the appropriate halide, using permanganate or manganese dioxide, is convenient. 

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