Hexane ethanol solution

The solvent used m catalytic hydrogenation is chosen for its ability to dissolve the alkene and is typically ethanol hexane or acetic acid The metal catalysts are insoluble m these solvents (or indeed m any solvent) Two phases the solution and the metal are present and the reaction takes place at the interface between them Reactions involving a substance m one phase with a different substance m a second phase are called het erogeneous reactions... 

BBT solution on unmodified sorbents of different nature was studied. Silica gel Merck 60 (SG) was chosen for further investigations. BBT immobilization on SG was realized by adsoi ption from chloroform-hexane solution (1 10) in batch mode. The isotherm of BBT adsoi ption can be referred to H3-type. Interaction of Co(II), Cu(II), Cd(II), Ni(II), Zn(II) ions with immobilized BBT has been studied in batch mode as a function of pH of solution, time of phase contact and concentration of metals in solution. In the presence of sodium citrate absorbance (at X = 620 nm) of immobilized BBT grows with the increase of Cd(II) concentration in solution. No interference was observed from Zn(II), Pb(II), Cu(II), Ni(II), Co(II) and macrocomponents of natural waters. This was assumed as a basis of soi ption-spectroscopic and visual test determination of Cd(II). Heavy metals eluted from BBT-SG easily and quantitatively with a small volume of HNO -ethanol mixture. This became a basis of soi ption-atomic-absoi ption determination of the total concentration of heavy metals in natural objects. 

The main obstacle to percntaneous penetration of water and xenobiotics is the onter-most membrane of the epidermis. This is called the stratum comeum. All entry of substances through the stratum comeum occurs by passive diffusion across several cell layers. The locus of entry varies, depending on the chemical properties of xenobiotics. Polar substances are believed to penetrate cell membranes through the protein filaments nonpolar ones enter through the hpid matrix. Hydration of the stratnm comenm increases its permeability for polar substances. Electrolytes enter mainly in a nonionized form, and thus the pH of the solution applied to the skin affects permeabUity. Many hpophdic substances, such as carbon tetrachloride and organophosphate insecticides, readily penetrate the stratum comeum. Pretreatment of the skin with solvents, snch as dimethyl sulfoxide, methanol, ethanol, hexane, acetone, and, in particular, a mixture of chloroform and methanol, increases permeability of the skin (Loomis, 1978). 

Balmer et al. [60] separated the two enantiomers of omeprazole on three different stationary phases with immobilized protein, viz, Chiral-AGP with a-1 acid glycoprotein, Ultron ES-OVM with ovomucoid, and BSA-DSC with BSA cross-linked into 3-aminopropyl silica using N-suc-cinimidyl carbonate. The mobile phase (1 ml/min) was phosphate buffer solution with 3—10% 2-propanol as the organic modifier. The enantiomers of omeprazole were separated on Chiralpak AD, an amylose-based chiral stationary phase, with ethanol-hexane (1 4) as mobile phase (1 ml/min). 

Phenyl THphenylgcrmyl Tellurium2 2.56 g (6.25 mmol) of diphenyl ditellurium are dissolved in a mixture of 3 ml of benzene plus 9 ml of ethanol, the solution is heated on a water bath, and, at reflux, a solution of 0.38 g (10 mmol) of sodium borohydride in 9 ml of 1 molar aqueous sodium hydroxide is added dropwise. When the red color of the mixture has faded, 5.1 g (15 mmol) of solid chlorotriphenylgermane are added quickly, the mixture is stirred for 5 min, and poured into 50 ml of water. The resultant mixture is extracted with three 70 ml portions of diethyl ether, the organic phases arc combined, dried with anhydrous sodium sulfate, filtered, and evaporated to dryness. The residue is recrystallized from hexane yield 3.9 g (61 %) m.p. 107°. Examples of similarly prepared compounds are ... 

Benzylidene-3-oxo-2,3-dihydrobenzotellurophene3 0.5 g (2 mmol) of 3-oxo-2,3-dihydrobenzotellurophene and 0.21 g (2 mmol) of benzaldehyde are dissolved in ethanol, the solution is stirred with cooling in an icc/water bath, and a solution of 0.2 g (5 mmol) of sodium hydroxide in ethanol is added dropwise. The resultant mixture is stirred for 0.5 h, water is added, and the precipitate is filtered olf, washed with water, dried, and recrystallized from hexane/benzene yield (not given) m.p. 140°. 

Natural sunlight induced photooxidation of naphthalene in aqueous solution has also been reported by McConkey et al. to produce six major products including 1-naphthol, coumarin, and two hydroxyquinone [9]. The authors proposed that the initially formed 2 + 2 and 2 + 4 photo cyclo addition products undergo subsequent oxidation and/or rearrangement to form the observed products [9]. Grabner et al. have studied solvent effects on the photophysics of naphthalene and report that fluorescence lifetime decreases by a factor of 2.5 in aqueous solution compared to organic solvents (e.g. ethanol, hexane, acetonitrile) [10]. Based on the observed differences in naphthalene excited triplet state properties in aqueous and organic media, the decrease... 

The method described above for the preparation of the mixture of 4-dodecylbenzenesulfonyl azides is new and based on the work of Bollinger and Hazen.5 7 Sulfonyl azides have been prepared by diazotizing substituted sulfonyl hydrazides,8 and treating sulfonyl halides in methanol-water,9 ethanol-water,10 acetone,2 5 7 or acetone-water solutions11 with aqueous or solid sodium azide,5 7 12 Use of phase transfer catalysis for the preparation of sulfonyl azides is new, simple and effective, ft avoids solvent changes and permits isolation of a hexane solution of sulfonyl azides without concentration. 

Solubility soluble 1 in less than 2 of water 1 in 30-40 of methanol practically insoluble in ethanol, -hexane, 1-butanol, acetonitrile, 2-propanol, and ethyl acetate. Viscosity (dynamic) 1.75mPas for a 8.5% w/w aqueous solution at 25°C, 1.09 mPas at 60°C ... 

Reduction of Aldehydes and Hydroperoxides. Stock solutions of approximately 100-200 ppm of 2-ethylhexanal in 95% ethanol, hexane, ana 2-ethylhexanol were prepared. Accurate carbonyl assays were conducted (ASTM method E411-70, "Trace Quantities of Carbonyl Compounds with 2,4-Dinitrophenylhydrazine ) initial carbonyl levels were... 

To a three-neck, 250-mL round-bottomed flask equipped with a water-jacketed condenser and nitrogen inlet and outlet lines were charged 75 g of ethanol, hexane, or 2-ethylhexanol solution. Magnetic stirrers were used to maintain constant agitation. In cases where reductions were accomplished at an elevated temperature (45°C), flasks were immersed in constant-temperature oil baths. Solutions were allowed to equilibrate with the surroundings before appropriate reducing agents were introduced. 

A mixture of 874 mg (2.40 mmol) of diiron nonacarbonyl, 918 mg (5.48 mmol) of 1-morpholinocyclohex-enc. and 510 mg (1.70 mmol) of 3,5-dibromo-2,6-dimethylhcptan-4-one in 5 mL of ben/.ene is heated at 32 JC with stirring for 12 h. The reaction mixture is diluted with 15 mL of EiOAe, then washed with 5 ml. of sat. NaHC03 followed by 5 mL of sat. NaCl. The organic layer is dried over Na,S04 and evaporated to give an oily material. This is treated with 3% ethanolic NaOH solution at 25 C for 10 min and quenched with water. The aqueous mixture is extracted with three 30-mL portions of EtOAc and then the organic extracts are dried. Removal of the solvents afforded an oil, which is subjected to preparative TLC (EtOAc/ hexane 1 10) to give the trans-product as colorless crystals yield 274 mg (73 %). Recrystallizalion produces an analytically pure sample mp 47-47.5 CC. 

Solutions of 0.52 g. (2 mmoles) of hydrated ruthenium trichloride in 20 ml. of ethanol, aqueous formaldehyde (20 ml., 40% w/v solution), and 0.6 g. of potassium hydroxide in 20 ml. of ethanol are added quickly and successively to a boiling solution of 3.14 g. (12 mmoles) of triphenylphosphine in 140 ml. of ethanol. The solution is heated under reflux for 15 minutes and then cooled. The resultant gray precipitate is separated, washed successively with ethanol, water, ethanol, and w-hexane, and then dried in vacuo. Yield 1.3 g. (70% based on RuC13 3H20). 

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