Sulfolane ethanol

CONSTANTS, VAPOR PRESSURES, ACTIVITIES, AND HEATS OF MIXING OF SULFOLANE-WATER, SULFOLANE-METHANOL, AND SULFOLANE-ETHANOL MIXTURES. 

Mild acid converts it to the product and ethanol. With the higher temperatures required of the cyano compound [1003-52-7] (15), the intermediate cycloadduct is converted direcdy to the product by elimination of waste hydrogen cyanide. Often the reactions are mn with neat Hquid reagents having an excess of alkene as solvent. Polar solvents such as sulfolane and /V-m ethyl -pyrrol i don e are claimed to be superior for reactions of the ethoxy compound with butenediol (53). Organic acids, phenols, maleic acid derivatives, and inorganic bases are suggested as catalysts (51,52,54,59,61,62) (Fig. 6). 

Steele, W.V., Chirico, R.D., Knipmeyer, S.E., and Nguyen, A. Vapor pressure, heat capacity, and density along the saturation line, measurements for cyclohexanol, 2-cyclohexen-l-one, 1,2-dichloropropane, 1,4-di-ferf-butyl benzene, (+)-2-ethyl-hexanoic acid, 2-(methylamino)ethanol, perfluoro-n-heptane, and sulfolane, / Chem. Eng. ilafa, 42(6) 1021-1036,1997a. 

Fig. 5. Plot of log(rates) vs. log(pressure) for rhodium-catalyzed CO hydrogenation. Reaction conditions 75 ml sulfolane, 3 mmol Rh, 1.25 mmol pyridine, H2/CO = 1, 240 C, 4 hr (96). Total rate includes rates to methanol, methyl formate, ethanol, ethylene glycol monoformate, and propylene glycol ( ) total ( ) methanol ( ) ethylene glycol. Open figures are for an experiment with H2/CO = 0.67.

Na-salt n=0, R=H, Li-salt) catalysts524 (the latter was used in polar solvents such as ethanol and sulfolane) or of terminal alkynes catalysed by Rh/tppms and Rh/42 (Table 3 n=2) systems.525... 

It is soluble with decomposition in water, and forms stable, deep-red solutions in acetone, ethanol, and concentrated hydrochloric acid. Early molecular-weight determinations in glacial acetic acid indicated a dimeric structure,8 but recent molecular-weight studies in Sulfolane have definitely established the existence of the trinuclear structure. X-ray crystallography also shows a trimer.9 Re3Cl9 reacts with a number of ligands to form complexes of the type LsRe Cl , where L = triphenyl-phosphine, pyridine, etc.10... 

Conductometric and spectrophotometric behavior of several electrolytes in binary mixtures of sulfolane with water, methanol, ethanol, and tert-butanol was studied. In water-sulfolane, ionic Walden products are discussed in terms of solvent structural effects and ion-solvent interactions. In these mixtures alkali chlorides and hydrochloric acid show ionic association despite the high value of dielectric constants. Association of LiCl, very high in sulfolane, decreases when methanol is added although the dielectric constant decreases. Picric acid in ethanol-sulfolane and tert-butanol-sulfolane behaves similarly. These findings were interpreted by assuming that ionic association is mainly affected by solute-solvent interactions rather than by electrostatics. Hydrochloric and picric acids in sulfolane form complex species HCl and Pi(HPi). ... 

Crystals of [Co(en)2(SCH2COO)] (C104) are dark purple, sometimes appearing black. The perchlorate salt, which crystallizes from the reaction mixture, is soluble in H20 (1.1 X 1CF2 M in 0.01 M HC104),S slightly soluble in dimethyl sulfoxide (DMSO), DMF, and sulfolane, and insoluble in ethanol. The chloride salt is very soluble in water and insoluble in all other solvents listed above. The (PF6) salt is soluble in DMSO, DMF, and tetrahydrothiophene 1,1-dioxide and insoluble in ethanol. The compound is characterized by its visible-UV spectrum,2C which has a peak at 518 nm (e = 152 M"1 cm-1) and a characteristic sulfur-to-metal charge-transfer band at 282 nm (e = 11,700 M1 cm 1) by which the purity of the compound can be estimated. 

It is to be noted that excellent agreement is found between tt and results and the earlier tt values for the following 21 solvents n-hexane, cyclohexane, triethylamine, isopropanol, dioxane, -propanol, ethanol, tetrahydro-furan, ethyl acetate, methyl acetate, ethyl formate, ethanol, methyl orthoformate, 2-butanone, acetone, acetic anhydride, nitromethane, dimethylacetamide, dimethylformamide, sulfolane, and dimethyl sulfoxide. The aromatic and polychlorinated aliphatic solvents give lower rr i and ir 2 results than the uv-based tt values (as expected in the light of the fact that these are really (ir + d5) terms all nmr shifts so far studied have involved negative d values in Equation 95). 

Hydrocarbons, such as hexane, heptane, and isooctane, may be used, but they have reduced solvent powers and are typically limited in use for the dissolution of nonpolar materials (the old rule of like-dissolves-like applies here). More polar solvent, such as alcohols (methanol, ethanol, isopropyl alcohol, etc.), dioxane, tetrahydrofuran, sulfolane, and dimethyl formamide, may be used for special applications, but it must be realized that the spectra of these solvents are very intense and often quite complex. As a result, there are limited windows of transparency at which measurements may be made. A number of excellent spectral collections have been published that feature solvent spectra (27-31), and it is recommended that the reader consult one of these texts before proceeding with a solvent-based method. 

The commonly used solvents for electrolytes are all dipolar and the dipole moments, n, of the molecules of these solvents range from 1.66D (ID (Debye unit)=3.33564 x 10 Cm) for ethanol and the two isomeric propanols to 5.54D for HMPT. Several of the solvents listed in Table 3.5 are very polar having dipole moments >4D propylene carbonate, y-butyrolactone, Af-methylpyrrohdinone, benzonitrile, nitrobenzene, dimethyl-sulfoxide, sulfolane, and HMPT. The polarizabihty a and the polarity (dipole moment) together with some chemical properties dealt with in Section 3.3 bear on the ability of the solvents to solvate the ions in electrolyte solutions. 

Alcohol Homologation Solvent and promoter effects on the cobalt carbonyl catalysed methanol homologation have been studied under synthesis gas pressure.The main product in a methanol/hydrocarbon two-phase system is 1,1-dimethoxyethane (ca. 70 selectivity).Using similar iodide promoted cobalt catalysts, R2C 0Me)2 and dimethylcarbonate are converted to acetaldehyde with up to 87 selectivity.Ruthenium in the presence of Co, 12 and dppe improves the ethanol selectivity in the homologation of dimethylether. Best results are achieved in inert solvents with high dielectric constants, e.g. sulfolane (e = 44), and with BF3 as activator. 

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