Cyclohexane acetonitrile mixture

Non-aqueous (or-oil-in-oil) emulsions, where the phases are two immiscible organic liquids, have received relatively little attention in the literature. Riess et al. [116-119] have studied the stabilisation of waterless systems with block and graft copolymers, where one of the liquids is a good solvent for one of the blocks and a non-solvent for the other, and vice versa. Thus, poly(styrene-b-methylmethacrylate) copolymers could emulsify acetonitrile/cyclohexane mixtures, and poly(styrene-b-isoprene) was effective for DMF/hexane systems [116]. These, however, are not HIPE systems. 

For reverse phase, common mobile phases are water, methanol, acetonitrile, and mixtures of these. Common stationary phases are phenyl, C8, and Cl 8. For normal phase, common mobile phases are hexane, cyclohexane, and carbon tetrachloride. Common stationary phases are structures that include cyano, amino, and diol groups. 

The results for (cyclohexane + decane) are obtained from J. R. Goates. J. R. Ott, and R. B. Grigg, "Excess Volumes of Cyclohexane 4- u-Hexane. +u-Heptane, -t-n-Octane, + -Nonane, and +u-Decane", J. Chem. Thermodyn.. 11. 497-506 (1979). Excess volumes for the (ethanol + water) system were obtained from K. N. Marsh and A. E. Richards, Excess Volumes for Ethanol + Water Mixtures at 10-K intervals from 278.15 to 338.15 K", Ausr. J. Chem., 33, 2121-2132 (1980). Excess volumes for the (acetonitrile + benzene) and the (hexane + decane) systems were obtained from the same source as the HG and results referenced earlier. 

Photolysis of several 2-azidophenazines has been shown to afford quinoxahnes. Thus irradiation of 2-azidophenazine (576, R = H) in cyclohexane or acetonitrile gave, among other products, 3-(2-cyanovinyl)-2-quinoxalmecarbaldehyde (577) in <17% yield and irradiation of 2-azido-l-methoxyphenazine in degassed benzene or acetonitrile gave, among other products, a separable mixture of cis- and frawi-isomers of methyl 3-(2-cyanovinyl)-2-quinoxalinecarboxylate (578), each in low yield. 3 ... 

B. 2,2-(Trimethylenedithio)cyclohexanone. A solution of 3.02 g. (0.02 mole) of freshly distilled 1-pyrrolidinocyclohexene, 8.32 g. (0.02 mole) of trimethylene dithiotosylate4 (Note 2), and 5 ml. of triethylamine (Note 3) in 40 ml. of anhydrous acetonitrile (Note 4), is refluxed for 12 hours in a 100-ml., round-bottom flask under a nitrogen atmosphere. The solvent is removed under reduced pressure on a rotary evaporator, and the residue is treated with 100 ml. of aqueous 0.1 N hydrochloric acid for 30 minutes at 50° (Note 5). The mixture is cooled to ambient temperature and extracted with three 50-ml. portions of ether. The combined ether extracts are washed with aqueous 10% potassium bicarbonate solution (Note 6) until the aqueous layer remains basic to litmus, and then with saturated sodium chloride solution. The ethereal solution is dried over anhydrous sodium sulfate, filtered, and concentrated on a rotary evaporator. The resulting oily residue is diluted with 1 ml. of benzene and then with 3 ml. of cyclohexane. The solution is poured into a chromatographic column (13 x 2.5 cm.), prepared with 50 g. of alumina (Note 7) and a 3 1 mixture of cyclohexane and benzene. With this solvent system, the desired product moves with the solvent front, and the first 250 ml. of eluent contains 95% of the total product. Elution with a further 175 ml. of solvent removes the remainder. The combined fractions are evaporated, and the pale yellow, oily residue crystallizes readily on standing. Recrystallization of this material from pentane gives 1.82 g. of white crystalline 2,2-(trimethylenedithio)cyclo-hexanone, m.p. 52-55° (45% yield) (Note 8). 

As a polar solvent for the catalyst ethylene carbonate (EC), propylene carbonate (PC) and acetonitrile were used. Tricyclohexylphosphine, triphenyl-phosphine and the monosulfonated triphenylphosphine (TPPMS) were investigated as ligands with Pd(acac)2 as the precursor. Cyclohexane, dodecane, p-xylene and alcohols (1-octanol, 2-octanol and 1-dodecanol) were tested as non-polar solvents for the product. To determine the distribution of the product and of the catalyst, the palladium precursor and the hgand were dissolved in the polar solvent and twice as much of the non-polar solvent was added. After the addition of 5-lactone, the amounts of the product in both phases was determined by gas chromatography. The product is not soluble in cyclohexane and dodecane, more than 99% of it can be found in the polar catalyst phase. With the alcohols 1-octanol, 2-octanol and dodecanol about 50 to 60% of the 5-lactone are located in the non-polar phase. With p-xylene biphasic systems can only be achieved when EC is used as the polar solvent and even in this solvent system one homogeneous phase is formed at a temperature higher than 70 °C. In a 1 1 mixture of EC and p-xylene about 50 to 60% of the product is contained in the polar phase. 

Sato et al. [42] measured resonance Raman spectra of 6-nitro-BIPS solid aggregates. They assigned the aggregates that they collected from cyclohexane as being the same as Takahashi groups mixture of isomers in acetonitrile [57] (not cyclohexane) because their spectra were similar. Sato et al. concluded that the aggregates were pure merocyanines with no ring-closed form present. 

Solvents 1 and 2 are known to be good solvents for poly(methyl methacrylate) solvent 3 readily dissolves polystyrene.The solubility tests show that the radically polymerized sample is insoluble in all three solvents.The solubility isthusdifferentfrom that of both poly(methyl methacrylate) and polystyrene.The anionically polymerized product dissolves on warming in the acetone/methanol mixture and also in acetonitrile it is insoluble in cyclohexane/toluene.The solubility is thus similar to that of poly(methyl methacrylate). For the cationically initiated polymerization the product is only slightly soluble in acetone/methanol, insoluble in acetonitrile, but very readily soluble in cyclohexane/toluene.The solubility thus resembles that of polystyrene. 

By far the most commonly used - though not the most environmentally friendly -solvent is CCl (or more usually water-CCl ). In a classic paper Sharpless et al. showed that oxidation reactions of RuO (and other some Ru-based oxidants) were accelerated by addition of a little acetonitrile to the conventional water-CCl biphasic mixture. It was suggested that the CH3CN might function as a mild donor stabilising a lower oxidation state carboxylato Ru species which could be involved in the catalytic process [260]. A comparative study of CCl, acetone, ethyl acetate, cyclohexane and acetone for cleavage of alkenes and alkynes by RuClg/aq. IO(OH)3/solvent showed that cyclohexane was the most effective [216]. Other solvents sometimes... 

Cyclohexane is more environmentally acceptable than the more commonly-used CCl. A recent cleavage of a mono-fluorinated alkene to a ketone was thus effected. The alkene (70 mg, 0.28 mmol) was dissolved in a mixture of acetonitrile (0.5 cm ) and cyclohexane (0.5 cm ) and treated with RuClj.nH O (0.05 g, 0.2 mmol) and Na(lO ) (0.24 g, 10 mmol) in water (1 cm ). The mixture was stirred for 1.5 h, the product extracted with diethylether and dried over MgSO [330]. Other examples, using RuCyaq. 10(0H)j/CgHj2-CH3CN have been given [216]. 

Cooper and Waters (13) first reported the oxidation of cyclohexane by cobalt(III) perchlorate in aqueous acetonitrile to give a mixture of cyclohexanol, cyclohexanone, and adipic acid. A more detailed study of this oxidation (74), using cobalt(III) acetate in acetic acid at 80°C, both with and without oxygen, gives products, such as cyclohexylacetate, that can only be explained if there is a direct interaction of cobalt(III) with the C—H [Pg.182]

The photo-induced electron transfer of l,4-bis(methylene)cyclohexane in acetonitrile-methanol solution with 1,4-dicyanobenzene (DCB) affords two products, both consistent with nucleophilic attack on the radical cation followed by reduction and protonation or by combination with DCB ).63 In the absence of a nucleophile, the product mixture is highly complex, as is the case under electro-oxidative conditions. Under UV irradiation, /nmv-stilbene undergoes dimerization and oxygenation (to benzaldehyde) by a single-electron mechanism in the presence of a sensitizer such as 2,4,6-triphenylpyrilium tetrafluoroborate (TPT).64 This reaction was found to yield a similar product mixture with the sulfur analogue of TPT and their relative merits as well as electrochemical and photophysical properties are discussed. 

Figure 17.13a shows H for the (cyclohexane + acetonitrile) system at (1), T = 348.15 K and (2), T = 323.15 K. At the higher temperature, a large positive is obtained, as expected for a (nonpolar + polar) mixture. At the lower temperature, (liquid + liquid) phase equilibrium with phase separation is present and a break occurs in the curve. The breaks at points (i) and (ii) are at compositions corresponding to the solubilities given by the (liquid + liquid) phase diagram shown in Figure 17.13b. Breaks in H curves such as at (i) and...

---