Alkanes oxidative

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]... 

The PDMS-membrane-occluded FePcY was the first room temperature catalytic membrane and the first solid catalyst dispersed in dense organic polymer.169 The catalytic system mimics the cytochrome P-450 enzyme and can oxidize alkanes at room temperature with rates comparable to those of the... 

Aldehydes do not co-oxidize alkanes due to a huge difference in the reactivity of these two classes of organic compounds. Alkanes are almost inert to oxidation at room temperature and can be treated as inert solvents toward oxidized aldehydes [35]. Olefins and alkylaromatic hydrocarbons are co-oxidized with aldehydes. The addition of alkylaromatic hydrocarbon (R2H) to benzaldehyde (R1H) retards the rate of the initiated oxidation [36-39]. The rate of co-oxidation obeys the equation [37] ... 

Ru(H20)(bpy)(app)]Clj (H3app=A-(hydroxyphenyl)pyridine-2-carboxaldimine) is made by reaction of RuClj with 2-aminophenol and 2-pyridine carboxaldehyde under reflux followed by addition of (bpy). Infrared and electronic spectra were measured, and the room-temperature magnetic moment is 1.98 B.M. The system [Ru(H30)(bpy) (app)] +/TBHP/(BTBAC)/CH3Clj (BTBAC=benzyltributylammonium chloride) oxidised benzyl alcohol to benzaldehde and alkenes to mixtures (e. g. cis- and trans-stilbene to benzaldehyde and cis- and tranx-stilbene oxides). Alkanes gave mixtures... 

Finally, it may be noted that the manganese and chromium oxyanions (permanganate and chromate) are known to oxidize alkanes readily (102). In these reactions there is not any direct interaction between the transition metal and the alkane the favored mechanism for chromate oxidation is... 

Indeed, it is not necessary for the central atom of the oxyanion to be a transition metal another atom with two different oxidation states is also effective. Recently, it has been found that, in trifluoroacetic acid solution, periodic acid oxidizes alkanes to low carbon number carboxylic acids (55). 

Metallic oxidants, namely, chromic acid and potassium permanganate, may be used to oxidize alkanes to alcohols or ketones, but these reagents have only limited synthetic value. Alkaline KMnC>4 is rather ineffective, mainly because of the insolubility of alkanes in the aqueous solution of the reagent. Oxidations in acidic solutions such as aqueous CF3COOH,108 or the use of special reagents such as benzyltriethylammonium permanganate109 may give better results. 

In different models for cytochrome P-450, Zn,152 Zn amalgam,153 and sodium ascorbate154 are used as the reductant. In contrast with all the abovementioned metal complex-catalyzed oxidations, the Mn(TPP)Cl-ascorbate system oxidizes alkanes with predominant formation of ketones.154 Certain complexes, however,... 

Lead(IV)277 and silver(III)301 trifluoroacetates in TFA also oxidize alkanes at room temperature to give alkyl trifluoroacetates [see also Section III.D.3 for reactions of alkanes with Pd(II) trifluoroacetate]. The stoichiometric oxidation of cyclohexane to a mixture of cyclohexanol, cyclohexanone, and adipic acid by cobalt(III) perchlorate in aqueous acetonitrile has also been reported.240... 

In the majority of these reactions, higher valent (Mn,v or Mnv) compounds have been implicated in the respective reactions (vide supra). As mentioned previously, two p-oxo Mn,v porphyrin species have been characterized from the reaction of iodosylbenzene with Mn111 compounds of the type [MnX(TPP)].678,690 These latter compounds are capable of oxidizing alkanes in good yield at room temperature, apparently via the intermediacy of alkyl free radicals.693... 

Cobalt(in) perchlorate in aqueous MeCN oxidizes alkanes at room temperature with an apparent secondary > primary > tertiary selectivi pattnm. This pattnm may not be real, however, because die product of tertiary attack may be much more sensitive to further oxidation. 2-Methylpentane was... 

Mnch of the reaction chemistry of alnminnm trialkyls can be classified by the following reaction types, some of which are illnstrated in Scheme 1 oxidation, alkane elimination in the presence of protic reagents, Al-C bond cleavage via halogenation and hydrogenation, insertion reactions, j6-hydrogen elimination (eqnation 5), and coordination of Lewis bases. 

Shilov chemistry, developed from 1970, employs [Pt(II)CLt] salts to oxidize alkanes RH to ROH or RCl with modest efficiency. Pt(IV) is an efficient (but economically impractical) primary oxidant that makes the process catalytic. This discovery strongly contributed to the continuing activity in CH activation. Periana developed a related and much more efficient system for methane oxidation to methanol using 2,2 -bipyrimidine ligands and sulfuric acid as solvent. In this case, the sulfuric acid is the primary oxidant and the methanol formed is protected by being converted in situ to MeOSOsH, an ester that strongly resists further oxidation. This area is more fully described under the entry Alkane Carbon-Hydrogen Bond Activation. 

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