Alcohols organic solvents

Harden, L., Bengtsson, N.O., Jonsson, U., Erikssonn, S. Larsson, L.G. (1984) Aetiological aspects of primary liver cancer with special regard to alcohol, organic solvents and acute intermittent porphyria—an epidemiological investigation. Br. J. Cancer. 50, 389-397... 

Johns et al. (2000) reported an anion exchange technology using Amberlite or Dowex or other resins to isolate phytoestrogens from plant protein materials. Carbonate or bicarbonate was used as a counterion to avoid chlorides or alkali in the final product. Protein slurry was passed through the column at pH 6-8. The bound isoflavones were released with alcohols, organic solvents or acid or base solution. The protein isolate produced was essentially free of isoflavones. 

Several inorganic and organic compounds such as nitrite, nitrate, phenols, alcohols, organic solvents, and aromatic hydrocarbons are known to be interferents in the chromotropic acid method were investigated. No interferences were observed from these compounds even at high concentration (1,000 pg/ml). Some... 

Most liquid-phase oxidation reactions were performed in water, sometimes on highly concentrated solutions, e. g. for glucose up to 1.7 mol L [61]. For water-insoluble alcohols, organic solvent could, in principle, be used, but most should be strictly avoided for safety reasons. Acetic acid was, however, used as solvent for the oxidation of retinol (3,7 dimethyl-9-(2,6,6-trimethyl-l-cyclohexe-nyl)-2,4,6,8-nonatetraen-l-ol) to retinal [84], Oxidation of water-insoluble molecules can be performed in the presence of surfactants [50]. 

Crystals, mp 139-140. Bitter taste. Slightly sol in cold water moderately sol in hot water. Freely sol in alcohol, organic solvents. 

In the commercial extraction of alkaloids from the drugs in which they exist, the powdered drug, or an alcoholic extract of it, is treated with an alkali such as ammonia or lime to liberate the alkaloid and the alkaloid is then extracted by means of an organic solvent. The crude material thus obtained is purified and finally crystallized either as the base itself or as its water-soluble salts. 

Like bromine, iodine is soluble in organic solvents, for example chloroform, which can be used to extract it from an aqueous solution. The iodine imparts a characteristic purple colour to the organic layer this is used as a test for iodine (p. 349). NB Brown solutions are formed when iodine dissolves in ether, alcohol, and acetone. In chloroform and benzene a purple solution is formed, whilst a violet solution is produced in carbon disulphide and some hydrocarbons. These colours arise due to charge transfer (p. 60) to and from the iodine and the solvent organic molecules. 

Solid carbon dioxide (Dry Ice, Drikold) is employed when very low temperatures are required. If it is suspended in solvents, such as alcohol or a mixture of equal volumes of chloroform and carbon tetrachloride, temperatures down to — 50° can be easily attained. Lower temperatures still are reached if intimate mixtures of solid carbon dioxide and organic solvents are employed with ethyl alcohol, — 72° with... 

Nitrobenzene is an extremely versatile solvent, and may frequently be employed for the crystallisation of compounds which do not dissolve appreciably in the common organic solvents. The vapour is somewhat poisonous, so that recrystaUisations must be carried out in the fume cupboard. After the crystals have been collected, they should be washed with a volatile solvent, such as benzene, alcohol or ether, to remove the excess of nitrobenzene (compare Section 11,32). The only disadvantage of nitrobenzene as a solvent is that it has a pronounced oxidising action at the boihng point. 

Heat a little pseudo-saccharin chloride with excess of the anhydrous alcohol in a test-tube until hydrogen chloride is no longer evolved. Recrystallise from alcohol or other organic solvent. 

CO—C H,—CO—0—CHj—CHOH—CHj—OOC—CgH,—CO— These are comparatively soft materials and they are soluble in a number of organic solvents. Under more drastic conditions (200-220°) and with a larger proportion of phthahc anhydride, the secondary alcohol groups are esterified and the simple chains become cross-hnked three dimensional molecules of much higher molecular weight are formed ... 

The oxidation of higher alkenes in organic solvents proceeds under almost neutral conditions, and hence many functional groups such as ester or lac-tone[26,56-59], sulfonate[60], aldehyde[61-63], acetal[60], MOM ether[64], car-bobenzoxy[65], /-allylic alcohol[66], bromide[67,68], tertiary amine[69], and phenylselenide[70] can be tolerated. Partial hydrolysis of THP ether[71] and silyl ethers under certain conditions was reported. Alcohols are oxidized with Pd(II)[72-74] but the oxidation is slower than the oxidation of terminal alkenes and gives no problem when alcohols are used as solvents[75,76]. 

Sensitivity is also influenced by the sample s matrix. We have already noted, for example, that sensitivity can be decreased by chemical interferences. An increase in sensitivity can often be realized by adding a low-molecular-weight alcohol, ester, or ketone to the solution or by using an organic solvent. 

Physical Properties. Furfuryl alcohol (2-furanmethanol) [98-00-0] is aHquid, colorless, primary alcohol with a mild odor. On exposure to air, it gradually darkens in color. Furfuryl alcohol is completely miscible with water, alcohol, ether, acetone, and ethyl acetate, and most other organic solvents with the exception of paraffinic hydrocarbons. It is an exceUent, highly polar solvent, and dissolves many resins. 

Physical Properties. Tetrahydrofurfuryl alcohol (2-tetrahydrofuranmethanol) [97-99-4] (20) is a colorless, high-boiling liquid with a mild, pleasant odor. It is completely miscible with water and common organic solvents. Tetrahydrofurfuryl alcohol is an excellent solvent, moderately hydrogen-bonded, essentially nontoxic, biodegradable, and has a low photochemical oxidation potential. Most appHcations make use of its high solvency. The more important physical properties of tetrahydrofurfuryl alcohol are Hsted in Table 1. 

Uses. Tetrahydrofurfuryl alcohol is of interest in chemical and related industries where low toxicity and minimal environmental impact are important (134). For many years tetrahydrofurfuryl alcohol has been used as a specialty organic solvent. The fastest growing appHcations are in formulations for cleaners (135) and paint strippers (136), often as a replacement for chlorinated solvents (137). Other major appHcations include formulations for crop sprays, water-based paints, and the dyeing and finishing of textiles and leathers. Tetrahydrofurfuryl alcohol also finds appHcation as an intermediate in pharmaceutical appHcations. 

Most xanthene dyes are classified as basic dyes by their method of appHcation acid dyes can be produced by introduction of sulfonic acid groups. The fluoresceins, which contain carboxy and hydroxy substituents, are also acid dyes for coloration of silk. Some of the fluoresceins in which the carboxy group has been esterified, are soluble in alcohol or other organic solvents and can be classified as solvent dyes. Mordant dyes can be produced by introducing o-dihydroxy or sahcyhc acid groups (2), which when metallised can have very good lightfastness. 

In early work, vinyl chloride had been heated with stoichiometric amounts of alkaU alkoxides in excess alcohol as solvent, giving vinyl ethers as products (210). Supposedly this involved a Williamson ether synthesis, where alkaU alkoxide and organic haUde gave an ether and alkaU haUde. However, it was observed that small amounts of acetylene were formed by dehydrohalogenation of vinyl chloride, and that this acetylene was consumed as the reaction proceeded. Hence acetylene was substituted for vinyl chloride and only catalytic amounts of alkaU were used. Vinylation proceeded readily with high yields (211). 

Selectivity. Solvent selectivity is intimately linked to the purity of the recovered extract, and obtaining a purer extract can reduce the number and cost of subsequent separation and purification operations. In aqueous extractions pH gives only limited control over selectivity greater control can be exercised using organic solvents. Use of mixed solvents, for example short-chain alcohols admixed with water to give a wide range of compositions, can be beneficial in this respect (6). 

Aqueous mineral acids react with BF to yield the hydrates of BF or the hydroxyfluoroboric acids, fluoroboric acid, or boric acid. Solution in aqueous alkali gives the soluble salts of the hydroxyfluoroboric acids, fluoroboric acids, or boric acid. Boron trifluoride, slightly soluble in many organic solvents including saturated hydrocarbons (qv), halogenated hydrocarbons, and aromatic compounds, easily polymerizes unsaturated compounds such as butylenes (qv), styrene (qv), or vinyl esters, as well as easily cleaved cycHc molecules such as tetrahydrofuran (see Furan derivatives). Other molecules containing electron-donating atoms such as O, S, N, P, etc, eg, alcohols, acids, amines, phosphines, and ethers, may dissolve BF to produce soluble adducts. 

Difluoroethanol [359-13-7], F2CHCH2OH, is a colorless Hquid with an alcohol-like odor mp, 28.2°C, bp, 96°C d[, 1.3084 n], 1.3320 heat of combustion, —1026 kJ/mol(—245.3 kcal/mol). It is stable to distillation and miscible with water and many organic solvents. As expected, its acidity Hes between that of 2-fluoroethanol and 2,2,2-trifluoroethanol both ia the gas phase (25) and ia 50% aqueous ethanol solution (26), where its of 1.0 x 10 is about 4.8 times smaller than that of trifluoroethanol. 

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