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Benzene solution, oxidation

Metal oxide electrodes have been coated with a monolayer of this same diaminosilane (Table 3, No. 5) by contacting the electrodes with a benzene solution of the silane at room temperature (30). Electroactive moieties attached to such silane-treated electrodes undergo electron-transfer reactions with the underlying metal oxide (31). Dye molecules attached to sdylated electrodes absorb light coincident with the absorption spectmm of the dye, which is a first step toward simple production of photoelectrochemical devices (32) (see Photovoltaic cells). [Pg.73]

The rate of dimerization of nitrile A-oxides is strongly influenced by the nature of R. When R = Cl, Br, CO2 alkyl or COR, the nitrile A-oxide cannot be isolated nor obtained in solution for any appreciable time. Table 11 gives the approximate time required for complete dimerization of some nitrile A-oxides (335) to furoxans (336) in benzene solution at 18 °C (70E1169). Evidently, steric and electronic effects dramatically increase the stability... [Pg.66]

Tri-n-octylphosphine oxide [78-50-2] M 386.7, m 59.5-60°, pK jt <0. Mason, McCarty and Peppard [J Inorg Nuclear Chem 24 967 7962] stirred an O.IM solution in benzene with an equal volume of 6M HCl at 40° in a sealed flask for 48h, then washed the benzene solution successively with water (twice), 5% aq Na2C03 (three times) and water (six times). The benzene and water were then evaporated under reduced pressure at room temperature. Zingaro and White [J Inorg Nucl Chem 12 315 7960] treated a pet ether solution with aqueous KMn04 (to oxidise any phosphinous acids to phosphinic acids), then with sodium oxalate, H2SO4 and HCl (to remove any manganese compounds). The pet ether solution was slurried with activated alumina (to remove phosphinic acids) and recrystd from pet ether or cyclohexane at -20°. It can also be crystd from EtOH. [Pg.492]

The intermediacy of dipolar species such as 186 has been demonstrated by reaction of enamines with 2-hydroxy-1-aldehydes of the aromatic series (129). The enamine (113) reacts in benzene solution at room temperature with 2-hydroxy-1-naphthaldehyde to give the crystalline adduct (188) in 91 % yield. Oxidation with chromium trioxide-pyridine of 188 gave 189 with p elimination of the morpholine moiety. Palladium on charcoal dehydrogenation of 189 gave the known 1,2-benzoxanthone (129). [Pg.157]

Fullerols, C6o(OH) (n = 24-26), can be synthesized directly by aerobic oxidation of a benzene solution of Qq using an aqueous solution of NaOH containing a few drops of BimNOH as the most efficient catalyst the deep violet benzene solution rapidly decolorizes and a brown sludge precipitates further reaction with more water over a period of 10 h gives a clear red-brown solution from which the... [Pg.284]

This compound was boiled with 12 g of dry piperidine in 120 ml of absolute benzene for 12 hours under reflux, a total of 6 g of piperidine hydrochloride being separated out. This was filtered off and the benzene solution was concentrated by evaporation. The residue was taken up in a little chloroform and the solution was applied to a dry aluminum oxide column (according to Brockmann) it was thereafter extracted with chloroform. After concentrating the solution by evaporation, an oil was obtained, which was taken up in absolute diethylether. Introduction of dry HCI gas into the cooled solution gave a precipitate which was dissolved and allowed to crystallize from isopropanol/ether. MP 193° to 199°C. [Pg.1249]

Nitroso-5//-dibenz[/>,/]azepine (9, R = NO) is relatively stable to photolysis under argon, whereas in benzene solution in the presence of oxygen, irradiation induces an oxidative Fischer -Hepp-type rearrangement to 2-nitro-5//-dibenz[6,/]azepinc (10, R = N02), accompanied by ring contraction to acridine-9-carbaldehyde184 (see also Section 3.2.2.4.). [Pg.279]

Anions of hydroperoxides may be used to successfully obtain sulphones by the oxidation of sulphoxides in non-aqueous media, without the use of transition metal catalysts. This is in contrast to oxidations with peracids where aqueous media are invariably used. Thus, dimethyl sulphoxide was oxidized by the anion of cumene hydroperoxide in ethanol or benzene solution at room temperature in 90% yield66. The yield is very much dependent on the base used and decreases along the series ... [Pg.976]

Epoxyeyclohexanone has been prepared in 30% yield4 by epoxi-dation of 2-cyclohexen-l-one with alkaline hydrogen peroxide, using a procedure described for isophorone oxide (4,4,6-trimethyl-7-oxabicyclo[4.1.0]heptan-2-one).5 A better yield (66%) was obtained using f r/-butyl hydroperoxide (1,1-dimethylethylhydroperoxide) and Triton B in benzene solution.6 The procedure described here is simple and rapid. [Pg.55]

To illustrate the application of corresponding-states theory to polymer solution calculations, we consider two cases of sol-vent/polymer vapor-liquid equilibria. The first case we consider is that of the chloroform/polystyrene solution. The second is that of benzene/polyethylene oxide. [Pg.191]

It may be pointed out that dehydration of p hydroxy esters with fused potassium hydrogen sulphate, acetic anhydride, phosphoric oxide or with thionyl chloride in benzene solution leads to ap-unsitturated esters containing some Py-unsaturated ester the proportion of the latter depends not only upon the structure of the ester but also upon the dehydrating agent used. I>ehydration occasionally occurs during the reaction itself or upon attempted distillation. [Pg.874]

Obtaining of oxide film throu sedimentation or by electrophoretic depositing from water, alcohol, or benzene solution also makes it possible to produce a fairly thin film with sufficient sensitivity to adsorption of above particles. However, poor mechanical features of the films obtained are their major drawbacks. [Pg.172]

Larger substituents or fewer Si-H groups lead to compounds that are more stable and which may be distilled in air, for example, c-C6HuSiH3 and Bu"3SiH (11). Although Ph3SiH is stable in air, it is oxidized by 02 in benzene solution in the presence of benzoyl peroxide... [Pg.155]

Ethyl 2-(D-amiino-tetrahydroxybutyl)-5-methyl-4-furoate (5.5 g.) is mixed with 80 ml. of dry benzene and 20 ml. of glacial acetic acid, and cooled in ice plus water. While stirring and cooling, 182 g. of lead tetraacetate (purity, 99.7%)62 is added during about sixty minutes stirring is continued until all the oxidant has been consumed. The lead dioxide is then removed by filtration, and the benzene solution is extracted twice with water.58 The benzene layer is dried with calcium chloride and the solvent is evaporated under diminished pressure, giving an oily residue which rapidly crystallizes in colorless plates yield, 3.6 g. (quantitative). The product is purified by recrystallization from dilute acetic acid or by steam distillation m.p., 57°. [Pg.129]

Mayo [138] proposed that PIP degradation occurs as a result of unstable alkoxyl radicals formed in oxidized polymer. Tobolsky [139] cleared that the degradation rate vs in experiments on PIP oxidation in a benzene solution is proportional to the initiation rate vs Vi. [Pg.480]

Oxidation of evermicose (122) with bromine yielded a mixture of y- and <5-lactones, which was directly acetylated. Refluxing the acetate in benzene solution in the presence ofp-toluenesulfonic acid gave (176) a mixture of the unsaturated lactones 131 and 132. In related work, Ganguly and Saksena (177) obtained an enonolactone by oxidation of D-nogalose with Jones reagent, followed by -elimination promoted by piperidine. Similarly, L-no-galose gave the enantiomeric lactone. [Pg.162]


See other pages where Benzene solution, oxidation is mentioned: [Pg.735]    [Pg.847]    [Pg.452]    [Pg.437]    [Pg.166]    [Pg.571]    [Pg.359]    [Pg.427]    [Pg.431]    [Pg.120]    [Pg.262]    [Pg.986]    [Pg.94]    [Pg.228]    [Pg.264]    [Pg.103]    [Pg.108]    [Pg.11]    [Pg.120]    [Pg.262]    [Pg.986]    [Pg.735]    [Pg.847]    [Pg.36]    [Pg.37]    [Pg.38]    [Pg.215]    [Pg.679]    [Pg.301]    [Pg.149]    [Pg.101]    [Pg.97]    [Pg.60]   
See also in sourсe #XX -- [ Pg.240 ]




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