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Solvent benzene-ethanol

Approximate abundance of humic substances was reported by the author (Ishiwatari, 1970 Ishiwatari et al., 1966). Air-dried sediment samples from Japanese lakes (Lakes Haruna, Shoji, Nishinoumi, Yamanaka, Nakatsuna, and Kizaki) were extracted by organic solvent (ethanol-benzene or methanol-acetone-benzene). Humic substances were then extracted from the preextracted sediment with 0.1 Al NaOH solution for two different extraction durations (6 hours and 1 month). The summarized results given in Table 1 indicate that humic substances extracted over a 1-month period amounted to... [Pg.149]

Thiophenols in organic solvents (ethanol, benzene, hexane) are rapidly oxidised by NO [55]. The reaction is exothermic and becomes quite hot if the rate of addition of NO is appreciable. A strong green colour develops immediately when the NO comes into contact with the thiophenol solution, and then fades to pale-yellow at the end of the reaction. This colour is due to the S-nitroso thiol. The following scheme of reaction has been proposed ... [Pg.160]

The Nenitzescu process is presumed to involve an internal oxidation-reduction sequence. Since electron transfer processes, characterized by deep burgundy colored reaction mixtures, may be an important mechanistic aspect, the outcome should be sensitive to the reaction medium. Many solvents have been employed in the Nenitzescu reaction including acetone, methanol, ethanol, benzene, methylene chloride, chloroform, and ethylene chloride however, acetic acid and nitromethane are the most effective solvents for the process. The utility of acetic acid is likely the result of its ability to isomerize the olefinic intermediate (9) to the isomeric (10) capable of providing 5-hydroxyindole derivatives. The reaction of benzoquinone 4 with ethyl 3-aminocinnamate 35 illustrates this effect. ... [Pg.150]

The extent of double-bond isomerization over homogeneous catalysts is influenced by choice of solvent. Saturation of the double bond in 4-(4-me-thoxyphenyl)-3-(2 nitro-4-methoxyphenyl)-l-pentene was achieved smoothly by reduction over RhCl(Ph3P)j in benzene wiihout any hydrogenation of the nitro function. If the solvent were benzene-ethanol, isomerization of the double bond to a conjugated position also occurred ihis styryl bond was inert to reduction under these conditions (77). [Pg.33]

Regardless of substrate and solvent, isomerization fell in the order 5% Pd-on-C 5% Rh-on-C > 5% Pt-on-C, and, regardless of substrate or catalyst, isomerization fell with solvent in the order ethanol > pentane > 1 1 benzene-ethanol. Benzene is effective as an isomerization inhibitor mixed with other solvents as well 1 20 benzene-acetone showed marked inhibition. Substituted benzenes are less effective than benzene. [Pg.34]

The main method for the preparation of different types of organostannanes is the ancient Wilrtz reaction between triorganotin halides or diorganotindihalides. Reactions proceed with or without solvent. Usual solvents are benzene, toluene, xylene, diethyl ether and ethanol. Occasionally hquid ammonia is also used. The preferred metals for this reaction are sodium and lithium. In the case of triorganotin halides, the reaction leads to symmetric hexaorganoditin compounds72 ... [Pg.468]

Photolysis of PATE Films. Photolysis of 2-8 micron films of PATE on glass or steel under the full arc of a focused 450 Watt medium pressure mercury lamp for 10 minutes yields totally insoluble films in water and a variety of organic solvents. These include ethyl ether, MEK, MIBK, THF, carbon tetrachloride, cyclohexane, pyridine, methylene chloride, methoxy ethanol, benzene, xylenes and acetone. DMSO alone swelled the film. Upon soaking in warm water for 10 minutes, the films could be removed intact. [Pg.292]

Soluble in acetone, ethanol, benzene, ether (Weast, 1986), and many other solvents including methanol, propanol, and 2-butanone. [Pg.179]

Miscible with ethanol, benzene, chloroform, ether, carbon disulfide (U.S. EPA, 1985), petroleum ether, solvent naphtha, and volatile oils (Yoshida et ah, 1983a). [Pg.259]

Carboxybenzotellurophene A mixture of 15.5 g (53 mmol) of 2-formylphenyl car-boxymethyl tellurium, 50 niL of pyridine and 50 niL of acetic anhydride is heated under reflux for 2 h. Most of the solvent is then evaporated under vacuum, and the residue is extracted with boiling of 1 M aqueous sodium hydroxide solution. The extract is neutralized, the precipitate is filtered off and the solid is recrystallized from ethanol/benzene. Yield 11.6 g (80%) m.p. 206-208°C. [Pg.294]

TelluranthreneP Finely powdered tellurium (2.3 g, 18 mmol) and 2.5 g (9.0 mmol) of o-phenylenel mercury are intimately mixed by grinding in a mortar, the mixture is placed in the well of a sublimation apparatus, which is then evacuated to <1 torr. The well of the sublimation apparatus is heated at 250°C in a bath of Wood s metal for 10 h, and the cold finger is cooled with dry ice. The sublimed solids are dissolved in chloroform, the solution is decanted through a filter, the solvent is evaporated, and the residue is recrystaUized from carbon tetrachloride or ethanol/benzene. Yield 1.05 g (57%). m.p. 179°C. [Pg.318]

Similar results were achieved when benzene was reduced with alkali metals in anhydrous methylamine at temperatures of 26-100°. Best yields of cyclohexene (up to 77.4%) were obtained with lithium at 85° [396]. Ethylamine [397] and especially ethylenediamine are even better solvents [398]. Benzene was reduced to cyclohexene and a small amount of cyclohexane [397, 398] ethylbenzene treated with lithium in ethylamine at —78° gave 75% of 1-ethyl-cyclohexene whereas at 17° a mixture of 45% of 1-ethylcyclohexene and 55% of ethylcyclohexane was obtained [397], Xylenes m- and p-) yielded non-conjugated 2,5-dihydro derivatives, l,3-dimethyl-3,6-cyclohexadiene and 1,4-dimethyl-1,4-cyclohexadiene, respectively, on reduction with sodium in liquid ammonia in the presence of ethanol (in poor yields) [399]. Reduction of diphenyl with sodium or calcium in liquid ammonia at —70° afforded mainly 1-phenylcyclohexene [400] whereas with sodium in ammonia at 120-125° mainly phenylcyclohexane [393] was formed. [Pg.48]

Id) Solubility Slightly soluble in water (1 g/350 mL at 25°C) miscible with methanol, ethanol, benzene, diethyl ether, petroleum ether, carbon tetrachloride, chloroform, carbon disulfide, dimethylformamide and oils. Has the highest solvent power of the chlorinated hydrocarbons (Lide, 1995 Budavari, 1996)... [Pg.817]

The reaction between 1,3-dicarbonyl compounds 1 and hydrazines is the most general method for preparing l//-pyrazoles 2 (Scheme 2).2-4,5 If a 2,2-disubstituted 1,3-diketone is employed (1 R3, R4 H), reaction with hydrazine hydrate gives instead a 4//-pyrazole 3, as was first reported by Knorr.Sa Generally, the reactants are heated under reflux in a solvent such as methanol, ethanol, benzene, or carbon tetrachloride yields range from 50% to quantitative. [Pg.55]

Many papers concerning salt effect on vapor-liquid equilibrium have been published. The systems formed by alcohol-water mixtures saturated with various salts have been the most widely studied, with those based on the ethyl alcohol-water binary being of special interest (1-6,8,10,11). However, other alcohol mixtures have also been studied methanol (10,16,17,20,21,22), 1-propanol (10,12,23,24), 2-propanol (12,23,25,26), butanol (27), phenol (28), and ethylene glycol (29,30). Other binary solvents studied have included acetic acid-water (22), propionic acid-water (31), nitric acid-water (32), acetone-methanol (33), ethanol-benzene (27), pyridine-water (25), and dioxane-water (26). [Pg.91]

Photolysis of GAV. A typical CIDEP spectrum of the laser photolysis of a static solution of GAV in a 1 3 ethanol / benzene solvent is shown in Figure 3a. The... [Pg.105]

A solution of perfluoroalkyl iodide (0.4 mmol), a-chlorostyrene (1.2 mmol) and Bu3SnSnBu3 (0.44 mmol) in benzene (3 ml) was irradiated using a metal halide lamp (National Sky-beam MT-70) in Pyrex tube under 02 atmosphere for 5 h. After removal of the solvent, ethanol and hydrazine acetate were added. The resultant solution was stirred under refluxing conditions for 2 h. After removal of the solvent, the residue was chromatographed on silica gel using a mixture of hexane and dichloromethane as an eluent, to give perfluoroalkylated pyrazole in 59% yield [117]. [Pg.142]

The insolubilized DIOP catalyst (34) was found to be rather ineffective for the asymmetric hydrogenation of oleflnic substrates the hydrogenation of a-ethyl-styrene proceeded readily but gave (-)-R-2-phenylbutane with an optical purity of only 1.5%. Methyl atropate was hydrogenated to (+)-S-methylhydratropate (2.5% ee). The soluble DIOP catalyst gave 15 and 17% ee, respectively, for the same reductions. The optical purity of the products was lower when recovered insolubilized catalyst was used. There was no reduction of a-acetamidocinnamic acid in ethanol-benzene with the insolubilized catalyst, presumably due to the hydrophobic nature of the polymer support causing it to shrink in hydroxylic solvents. [Pg.105]

Reductions were carried out in a 1 1 ethanol-benzene solvent, at 300 psi H2, for 24 hr at 60°C. The solvent was deoxygenated immediately prior to use. The catalyst was formed in 100 ml of solvent from 34 jumole of [Rh(COD)Cl] 2 and 0.5 mmole of phosphine, was prereduced for 0.5 hr at 3.5 atm H2, and then the substrate (most often 25 mmole a substrate-rhodium ratio9 of 375)was added in 100 ml of solvent containing 4 mmole of triethylamine. [Pg.107]

A kinetic study of the hydrogenation of benzhydrol to diphenyl-methane (Wender, Greenfield, Metlin, Markby and Orchin, 21) in different solvents showed that the rate decreased in the following order ethanol > benzene > cyclohexane. This is the solvent effect to be expected in a reaction with an ionic intermediate. Furthermore, the reduction is completely inhibited with pyridine as a solvent, a fact consistent with acid catalysis. [Pg.412]

The wood specimen is ground to pass a 0.4 mm (40-mesh) screen. A sample of the wood meal equivalent to about 5 g on an oven-dry basis is placed in a coarse porosity alundum or fritted glass extraction thimble and extracted successively in a Soxhlet apparatus with ethanol-benzene for 6-8 h and 95% ethanol for 4h. Between extractions the wood meal is transferred to a Buchner funnel, where the excess solvent is removed by suction and washing with ethanol. [Pg.34]

Using a Wiley mill, wood samples are ground and the 40-60 mesh fraction is Soxhlet-extracted with ethanol benzene (1 2, v/v). Pulp samples are used without size reduction and are solvent exchanged with acetone before drying at 60 °C at 20 mm (Note 1). [Pg.44]

The oxathia[3.2]naphthalenophane 82 was obtained by Billen and Vogtle [78] in a yield as hi as 78 % by cyclization of the bis(bromomethyl) compound 81 with the reagent combination Na2S/Cs2Q03 in acetonitrile under dilution conditions. The choice of the solvent was of high importance If the cyclization was carried out not in acetonitrile [79] but in an ethanol/benzene mixture (1 1), the... [Pg.56]

Using the base CsOH in ethanol/benzene (12 1) as the solvent and the isothiuronium salt 96 increased the yield of the isomeric cyclic compounds 97 to 75 %. The... [Pg.58]


See other pages where Solvent benzene-ethanol is mentioned: [Pg.69]    [Pg.187]    [Pg.735]    [Pg.164]    [Pg.340]    [Pg.521]    [Pg.190]    [Pg.573]    [Pg.365]    [Pg.278]    [Pg.279]    [Pg.11]    [Pg.847]    [Pg.164]    [Pg.110]    [Pg.87]    [Pg.127]    [Pg.207]    [Pg.490]    [Pg.3728]   
See also in sourсe #XX -- [ Pg.28 , Pg.34 , Pg.35 , Pg.41 , Pg.44 , Pg.115 , Pg.124 , Pg.305 , Pg.324 , Pg.336 , Pg.356 , Pg.360 , Pg.376 ]




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