Benzotrifluoride oxidation

More drastic conditions of temperature, pressure and time gave carbon as the product from both aromatic and aliphatic compounds. This carbon is an activated char with decolorizing properties. Tars, tarry substances, the oxides of carbon, and the usual products of the oxidation of aromatic compounds (dicarboxylic acids) were all conspicuous by their absence. Benzotrifluoride oxidized to benzoyl fluoride. The aliphatic compounds cyclohexane, methycyclohexane, n-heptane, etc., could be oxidized to carbon and water. 

Muzart and coworkers investigated the CrOs/TBHP catalyzed oxidation of various benzylic methylenes and the allylic oxidation of A - and A -cholesten-3-one to the corresponding ketones in CH2Cl2 as well as benzotrifluoride (BTF) as solvent (Scheme 130) °. It could be shown that BTF in most cases improved the results even though the reactions were carried out with less TBHP than in CH2CI2 (4 eq. compared to 7 eq.). Yields in CH2CI2 varied from 21 to 94% and those in BTF from 40 to 99%. 

SCHEME 130. BenzyUc and allylic oxidation with CrOs in CH2CI2 or benzotrifluoride... 

Miyamura et al. [170] and Kanaoka et al. [171] have succeeded in stabilizing Au clusters on polymer supports for aerobic oxidation at room temperature in the mixed solvent of water-benzotrifluoride and in water, respectively. Polymer supports could also offer new functions, such as a recycling system by using a thermoresponsive polymer-supported Au catalyst [171]. 

In any event, 02SbF6 or 02AsF6 act as a very effective one-electron oxidant with regard to aromatic amines, nitrogen- and sulfur-containing heterocyclic compounds (Dinno-cenzo and Banach 1986, 1988, 1989), as well as perfluorobenzene, benzotrifluoride, and perfluoronaphthalene (Richardson et al. 1986). The oxidation proceeds in freon (CHCIF2) at temperatures from -115 to - 145°C, and the formation of the organic cation radicals has been firmly established. 

BENZOTRIFLUORIDE (98-08-8) Forms explosive mixture with air (flash point 54°F/12°C). Reacts with atmospheric moisture, water, steam, forming hydrogen fluoride and benzoic acid. Violent reaction with oxidizers, lithium. Explosive reaction with bis(trifluo-romethyl)sulfiide. 

Oxidations. A chromium-catalyzed oxidation of alcohols with sodium percarbonate is accomplished in benzotrifluoride. PhCF, is a useful replacement for 1,2-dichloroethane as solvent. 

Benzotrifluoride 1 is a colorless, low viscosity liquid. Its polarity is intermediate between those of dichloromethane and ethyl acetate, and it is miscible with common organic solvents and able to dissolve many organic compounds. Benzotrifluoride is used in a wide variety of reactions including radical reactions, oxidations and reductions, phase-transfer reactions, transition metal catalyzed processes and Lewis acid reachons. Ogawa and Curran reported that dichloromethane (CH2CI2) is replaceable by BTF in many instances [8]. 

Benzotrifluoride o-Chlorobenzotrifluoride p-Chlorobenzotrifluoride Dichlorotetrafluoroethane 1,2-Dichlorotetrafluoroethane Dimethicone Propionitrile Tetra-n-butoxysilane 1,2,3,4-Tetrachlorobenzene Tetrakis (2-ethylbutoxy) silane Tetrakis (2-ethylhexoxy) silane 1,3,5-Trichlorobenzene dielectric fluid, switch gears PerfIuorodecalin PerfIuoromethyldecalin dielectric fluid, transformers PerfI uorodecal i n PerfI uoromethyl decal i n dielectric gas Chloropentafluoroethane dielectric insulator, high-voltage cables Polyethylene, crosslinked dielectric layers in electronic circuits Tantalum oxide dielectric liquid Di butyl sebacate dielectric oils Silicone dielectrics... 

The oxidative carbonylation of benzotrifluoride to form trifluoromethylbenzoic acids has been described by Bell and Zakzeski [38]. By using a Pd(II) catalyst in combination with a carboxylic acid, ammonium metavanadate, CO, and O2, trifluoromethylbenzoic acid was achieved in good selectivity. Shi and his colleagues performed LiCl-promoted Pd(II)-catalyzed oxidative carbonylation of A(A-dim-ethylbenzylamines [39]. This reaction is highly regioselective and the product can be further transformed into ortho-methyl benzoate under mild conditions. 

The utilisation of Au-Pt-supported nanoparticles for the liquid-phase oxidation of a variety of alcohols has been presented with high yields (90-99%) of the corresponding aldehydes or ketones at room temperature, using atmospheric pressure and benzotrifluoride/water as the solvent (Eq. 22.15). A colloidal method was used for the synthesis of the metal nanoparticles. X-ray spectroscopy confirmed the presence of both metals in each nanoparticle and the particle size distribution was in the range of 1.5-5 nm. Catalysts were reused several times without loss of activity. 

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