Oxidations saturated hydrocarbon oxidation

Polyisobutylene and IIR have chemical resistance expected of saturated hydrocarbons. Oxidative degradation is slow and the material may be further protected by antioxidants, for example, hindered phenols. 

Chromyl chloride also oxidizes saturated hydrocarbons. For example, it oxidizes isobutane to tert-butyl chloride ... 

Part of the mystique surrounding the often assumed high reactivity of dioxiranes stems from the observation that dioxiranes such as methyl(trifluoromethyl)dioxirane (TFDO) are capable of oxidizing saturated hydrocarbons to their alcohols at relatively low temperatures in high yields and with impressive stereoselectivities (equation 8). 

The statements of the possible role of HO radicals in saturated hydrocarbon oxidation processes is proved by experimentally determined formation of sufficient amounts of hydrogen peroxide and HO radicals during oxidation of propane [27] and paraffin dehydrogenation products [28-30],... 

The anionic complex M2 [IrCl6] (M = Na and K) are commercially available and have been used as outer-sphere single-electron oxidants in mechanistic studies of the cleavage of metal-carbon bonds [218]. The isostructural oxidant [PtCle] is also known, especially its ability to oxidize saturated hydrocarbon by electrophilic C-H activation (inner-sphere two-electron oxidant) [219]. 

The low-pressure acetic acid process was developed by Monsanto in the late 1960s and proved successful with commercialization of a plant producing 140 X 10 metric tons per year in 1970 at the Texas City (TX, USA) site [21]. The development of this technology occurred after the commercial implementation by BASF of the cobalt-catalyzed high-pressure methanol carbonylation process [22]. Both carbonylation processes were developed to utilize carbon monoxide and methanol as alternative raw materials, derived from synthesis gas, to compete with the ethylene-based acetaldehyde oxidation and saturated hydrocarbon oxidation processes (cf. Sections 2.4.1 and 2.8.1.1). Once the Monsanto process was commercialized, the cobalt-catalyzed process became noncom-... 

O (nucleophilic) is necessary in allylic oxidation, and that the other species (electrophilic) are detrimental, by bringing about complete oxidation. On the other hand, some of these electrophilic species are very likely necessary for removing the first hydrogen of the saturated hydrocarbons (oxidation of butane to maleic anhydride and selective reactions of methane with oxygen). 

Ruthenium tetroxide formed from Ru02 2H20 or other mthenium derivatives and sodium periodate oxidize saturated hydrocarbons [74] ... 

The Gif system, which consists of triplet oxygen, acetic acid, pyridine, zinc and an iron catalyst, oxidizes saturated hydrocarbons mainly to ketones and gives minor amounts of aldehydes. Tertiary hydrogen is only substituted in exceptional cases. With the Gif-Orsay II system in which zinc is replaced by the cathode [divided cell, cpe at — 0.6 to —0.7 V vs see, trifluoroacetic acid, pyridine, Fe30(0Ac)6Pyr3.5], adamantane is converted in 3.8% coulombic yield the ratio of attack at a secondary tertiary CH bond (C /C ratio) is 15.0. Comparable conversions were carried out with cyclododecane to afford 21% oxidation with a ratio of alcohol ketone = 1 14. TranS decalin yielded 22% product, consisting of 0.6% 9-ol, 0.9% l-ol, 9.0% 1-on 0.65% 2-ol and 11% 2-one. A radical mechanism for this conversion can be excluded since for the cobalt-catalyzed radical oxidation of trans-decalin the C /C ratio is 0.13, which is far removed from 36 found with the Gif system. 

Barton and coworkers [121-123] have discovered multicomponent systems which have come to be known as Gif systems . They oxidize saturated hydrocarbons with molecular oxygen under ambient conditions. The main components of the systems are acetic acid (or other acid) in pyridine as solvent, iron powder as a source of electrons and a precursor of an iron catalyst. The compositions of the different variants and the probable functions of the individual components are listed in Table VI. 

Figure 20. Mechanism of saturated hydrocarbon oxidation catalyzed by Ru(porp)(CO)/pyNO systems S = substrate, X = the oxygen donor (OD) such as ChpyNO, or other ligands...

Palladiumdiacetate in trifluoroacetic acid (Pd(02CCF3)2) gives a mixture of o- and p-trifluoroacetoxylated products. The reagent is also capable of oxidizing saturated hydrocarbons such as adamantane and methane. In the presence of carbon monoxide and with sodium acetate as co-catalyst, carbonylation of aromatic C-H bonds occurs, eventually yielding acid anhydrides. ... 

All silver oxides, AgO, , x > 1, are very strong oxidants. They are soluble in cold nitric acid yielding dark brown solutions with the Ag ion complexed by NOj. These solutions will even oxidize saturated hydrocarbons. Both Ag20j and Ag304 decompose rapidly at temperatures of 50° and 60°, respectively. Even at room temperature, decomposition to AgO within a couple of hours is observed. Well-crystallized AgO, as obtained by electrocrystallization, is more stable and decomposes only above 160°. 

The significance of the total sulfur content of kerosene varies greatly with the type of oil and the use to which it is put. Sulfur content is of great importance when the kerosene to be burned produces sulfur oxides, which are of environmental concern. The color of kerosene is of Htde significance but a product darker than usual may have resulted from contamination or aging in fact, a color darker than specified may be considered by some users as unsatisfactory. Kerosene, because of its use as a burning oil, must be free of aromatic and unsaturated hydrocarbons the desirable constituents of kerosene are saturated hydrocarbons. 

Polyisobutylene has the chemical properties of a saturated hydrocarbon. The unsaturated end groups undergo reactions typical of a hindered olefin and are used, particularly in the case of low mol wt materials, as a route to modification eg, the introduction of amine groups to produce dispersants for lubricating oils. The in-chain unsaturation in butyl mbber is attacked by atmospheric ozone, and unless protected can lead to cracking of strained vulcanizates. Oxidative degradation, which leads to chain cleavage, is slow, and the polymers are protected by antioxidants (75). 

Manganese, copper, iron, cobalt and nickel ions can all initiate oxidation. Untinned copper wire can have a catastrophic effect on natural rubber compounds with which it comes into contact. Inert fillers for use in rubbers are usually tested for traces of such metal ions, particularly copper and manganese. The problem is perhaps less serious in saturated hydrocarbon polymers but still exists. 

Peroxytnfluoroacetic acid is used tor numerous oxidations of saturated hydrocarbons and aromatic compounds It oxidizes alkanes, alkanols, and carboxylic acids with formation of hydroxylation products [29] Oxidation of cyclohexane with peroxytnfluoroacetic acid proceeds at room temperature and leads to cyclohexyl trifluoroacetate in 75% yield, 1-octanol under similar conditions gives a mixture of isomeric octanediols in 59% yield, and palmitic acid gives a mixture of hydroxypalmitic acids in 70% yield [29]... 

Aeckersberg F, F Bak, F Widdel (1991) Anaerobic oxidation of saturated hydrocarbons to COj by a new type of sulfate-reducing bacterium. Arch Microbiol 156 5-14. 

This last comment is a warning on the potential risk that dinitrogen tetroxide presents as a reagent vis- i-vis the particular alcohol-acid. The paragraph on hydrocarbons confirms this. This oxide has even caused accidents with saturated hydrocarbons (these can be due to impurities). In any case, there is every chance that oxide will activate the methyl groups of this compound. 

The nature of dangerous reactions involving organic chemicals depends on the saturated, unsaturated or aromatic structures of a particular compound. Saturated hydrocarbons are hardly reactive, especially when they are linear. Branched or cyclic hydrocarbons (especially polycyclic condensed ones) are more reactive, in particular as with oxidation reactions. With ethylenic or acetylenic unsaturated compounds, the products are endothermic . 

The CH4/CI2 mixture is explosive if it contains more than 20% of chlorine. If mercury oxide is present, the reaction is very violent. The accidents mentioned below deal with saturated hydrocarbons. 

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