Fluorine oxide, reaction

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. 

It has to be considered that titanium - at least without special protection layers - will be attacked by several chemicals for example, fluorides, fluorine-containing substances, such as tetrafluo-roborates BF4, or oxalates, and possibly by other organic acids, which may be formed during anodic oxidation reactions. An application of titanium in nonaqueous media is not suitable (instability of the passivating oxide layer). 

In this example the solvent - a fluorinated alcohol - forms higher order aggregates and activates for the epoxidation of electron rich olefins. HFIP accelerates this oxidation reaction up to 100,000-fold (relative to that in 1,4-dioxane as solvent). Which hydrogen bond network involving olefin, and fluorinated alcohol gives rise to such spectacular accelerations ... 

A residue remains undecomposed above 893 K. The mass fraction of this residue is 0.656, whereas the mass fraction of Mg contained within the pyrolant is Mg(0-600). This indicates that the residue is produced by oxidation of the Mg by the fluorine produced upon thermal decomposition of the Tf An X-ray analysis revealed that the remaining residue above 893 K in the TG experiments consisted of Mg and Mgp2. The oxidation reaction during the decomposition of Mg-Tf pyrolants is thus ... 

One mole of Mg (24.31 g) reacts with one mole of fluorine gas (38.00 g) to form one mole of magnesium fluoride (62.31 g). Since the oxidation reaction occurs at the surface of each Mg particle, the particles become coated with an oxidized surface layer of Mgp2. The thickness of such an Mgp2 surface layer has been calculated as 0.19 pm.l l... 

Alternatively, fluorinated aminoesters with the enyne structure were transformed into a variety of vinyl cyclic amino acid derivatives and related bicydic derivatives via Diels-Alder and oxidation reactions [38] (Sdieme 8.6). 

Oxidative reactions of dienes are accomplished under similar conditions to those of alkcnes. Different oxidizing agents are used for dienes with nonfluorinated and fluorinated C = C bonds. Epoxidations are prevalent among oxidation reactions of dienes without C = C bond cleavage. Selective epoxidation or dihydroxylation of only one C = C bond can be achieved in particular cases. 

A number of oxidation reactions of mono- and difluorosteroid compounds has been reported. In some reactions, the specific influence of a fluoro substituent on the reactivity has been observed the presence of a 9a-fluorine in a 11 /i-hydroxy-A4-3-oxo steroid causes completely stcreospecific alkaline epoxidation with hydrogen peroxide in a much slower reaction (4d vs 4 h) in comparison with the nonfluorinated analog.322 Most oxidations are accomplished by the highest selective biochemical (that is, by bacterial enzymatic) transformations. As the biochemical oxidation systems are not discussed in this section, only a list of selected transformations of steroids is presented in Table 21. For additional information see ref 323. 

The well known ability of antimony pentafluoride to oxidize some elements, such as sulfur or selenium, to the corresponding polynuclear cations [1] found its application in the synthesis of fluorinated materials. Reaction of sulfur with TFE, HFP, and PFIB in the presence of SbF5 was reported [ 129,130] ... 

Oxidative fluorination.1 Reaction of phenol with Pb02 (2 equiv.) and HF/ pyridine (70/30, w/w) in CH2CI2 at 25° provides the dienone 1 in 30% yield. It can undergo Michael addition and aromatization to give substituted p-fluorophenols. 

An alternative method of preparing the SF5 group was developed in the 1990s using elemental fluorine and an arylthiol. In this process, elemental fluorine is used both as an oxidant and a fluorinating agent. Despite the fact that in the final fluorination, the conversion of SF3 to SF5 is difficult and results in a number of byproducts from ring fluorination side reactions, it provides a more realistic route to the preparation of many pentafluorosulfur phenyl derivatives (Fig. 40) [181],... 

For some oxidations, toxic heavy metal oxidants are used [313], This can be circumvented by the use of microreactor technology due to safe handling of elemental fluorine that can be used to mediate oxidation reactions [313], This is possible in a direct way via fluorine introduction into the substrate and subsequent replacement by an oxygen moiety. In an indirect manner, intermediate oxygen transfer reagents such as HOF MeCN can be generated by the reaction of aqueous acetonitrile with elemental fluorine that then attacks the substrate. The only byproduct is hydrogen fluoride that could be recycled by electrolysis. 

It rivals fluorine in the ability to stabilise the highest known oxidation states of many elements, examples where there is no corresponding fluoride being C1(VII)04- and Os(VIII)04. Oxidation reactions with 02 are often show because of the strength of the 0 = 0 double bond (490 kJ mol-1). 

Reaction Calorimeters. The previous discussion focused on oxidation reactions (oxygen and fluorine bomb calorimeters), but many other calorimeters of specialized design are used to monitor chemical reactions phase change, solution, and so on. 

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