3-Pyridine methanol/ethanol

The column eluent passes directly into a nebulizer, the outlet tube from the column terminating at the nebulizer nozzle. A portion of the atomized eluent passes directly into the electron capture detector and then out to waste. The detector is operated under the same conditions as those that would be used if it were being used as a GC detector. The work of Nota and Palombari established the system as viable and demonstrated that the solvents, benzene, hexane, cyclohexane, pyridine, methanol, ethanol, diethyl ether, and acetone could all be employed as... 

Water with ethanol, n-propanol and isopropanol, tcrt-butanol, propionic acid, butyric acid, pyridine, methanol with methyl iodide, methyl acetate, chloroform,... 

The phosphorodithioate is stable to heating at 100°, 80% acetic acid (1 h), dry or aqueous pyridine (days) and refluxing methanol, ethanol or isopropyl alcohol for Ih. 

However, in 1939 this difficulty was obviated by Brauns extraction of about 3% lignin from spruce wood by means of the solvent, ethyl alcohol, at room temperature (9). He termed this preparation native lignin. It was found to be soluble in methanol, ethanol, dioxane, dilute sodium hydroxide and pyridine, and insoluble in water, ether, petroleum ether and benzene. Chemically it behaved the same as lignin as it exists in woody tissues. It also reduced Fehling s solution and gave a strong... 

Wittig reaction (Benzene, toluene, methanol, ethanol, t-butanol, diethyl ether, DME, tetrahydrofuran, acetic acid, CH2CI2, pyridine, acetonitrile, DME, dimethylsulfoxide)... 

Solid Mo02Br2(DMF)2 melts at 139-141°C with decomposition. The IR spectrum, taken as a KBr dispersion, has characteristic bands for i moO 903 and 940 cm The NMR spectrum in acetone-t/g exhibits signals at S 3.03 (s, 3H, CHa), 3.22 (s, 3H, CH3), 8.26 (s, IH, CH). The complex is insoluble in hexane and diethyl ether and is soluble in methanol, ethanol, dichloromethane, chloroform, acetone, dimethyl formamide, and dimethyl sulfoxide. It is stable in air at room temperature and can be manipulated without special care. This product is specially useful for the synthesis of a number of adducts with pyridine and related bases, since the dimethyl formamide displaced can be readily removed by washing with most common organic solvents. 

Notes. (1) Pyridine was stored over potassium hydroxide and distilled immediately before use. The tris(cyclohexyl)phosphine-carbon disulphide complex is prepared by the method of K. Issleib and A. Brack.9 This involves the addition of carbon disulphide to an ethereal solution of tricyclohexylphosphine, the precipitate is washed with light petroleum (b.p. 50-60 °C), and recrystallised under a nitrogen atmosphere from either methanol, ethanol or dioxane the complex has m.p. 118 °C. 

Direct photolysis of 2-halopyridines in methanol, ethanol or acetonitrile (with 1% water) affords pyridine, together with alkoxy-, or hydroxypyridines376. The formation of the substitution products will be discussed in Section IV.C. The reductive dehalogenation is considered to proceed via homolysis of the carbon-halogen bond. The efficiency of pyridine formation decreases in the order Br > Cl > I. The 3- and 4-halopyridines produce pyridine exclusively. 

The intermediacy of a cation, formed by electron transfer within a photochemically created radical pair, was also invoked to explain the results obtained upon photolysis of 2-bromo-, 2-chloro- and 2-iodopyridine in methanol, ethanol and acetonitrile-water376. The major products are 2-methoxypyridine, 2-ethoxypyridine and 2-acetamidopyridine + 2-hydroxypyridine. In all cases pyridine was the minor reaction product, in contrast with the 3- and 4-halopyridines which produce pyridine exclusively, via a radical process. It is proposed that the unshared electron pair on the nitrogen atom assists in the formation of the 2-pyridyl cation. The presence of cupric salts increases the relative amounts of products formed via ionic reactions because Cu2+ can accept an electron from the 2-pyridyl radical. 

Recent work (Wender, Sternberg, and Orchin, 36) suggests a revision of the view (Hieber, Muhlbauer, and Ehmann, 37) that the reaction between dicobalt octacarbonyl and compounds like methanol, ethanol pyridine, and o-phenanthroline involves only the displacement of one or more carbon monoxide groups of the carbonyl by the base according to Equation (1), using pyridine as an example. 

The complexes are very soluble in methanol, ethanol, butanol, methyl Cellosolve (2-methoxyethanol), and ethyl Cellosolve (2-ethoxyethanol), and to a fair degree, quite soluble in 1,2-dimethoxyethane and di- and triglyme. They are initially quite soluble in tetrahydrofuran, acetone, pyridine, nitro-methane, acetonitrile, dimethyl sulfoxide, and iV,A/-dimethyl-formamide, but usually precipitation of the nickel halide-solvent complex occurs if attempts are made to prepare moderately concentrated solutions in these solvents. They are only very slightly soluble, or are quite insoluble in dioxane, ethyl ether, hexane, dichloromethane, ethyl acetate, and methyl- and butyl-cellosolve acetate (2-methoxyethyl and 2-butoxyethyl acetate). 

The completely substituted product is a white, granular, solid with mw 246 30 and mp 240—45°. Its method of prepn was described by Hess Muller (Ref 1). The triethylcellu-lose is insol in w and practically insol in methanol, ethanol acetone, but sol in chlf, pyridine, ethylene di chloride, ethyl acetate, carbon tetrachloride and many other organic solvents. This product has, however, no military or commercial application because it. lacks strength. flexibility, is not thermoplastic and shows only very limited compatibility... 

NERVE Methanol, ethanol, n-propanol, 2-hutanol, t-hutyl alcohol, ethyl acetate, 1,4-dioxane, acetonitrile, acetaldehyde, V,V-dimethylformamide, pyridine... 

To 0.5 mL of the stock solution of semicarbazide hydrochloride, which contains 1 millimole of the reagent, add 1 millimole of the compound to be tested and enough methanol (1 mL) to produce a clear solution then add 10 drops of pyridine (a twofold excess) and warm the solution gently on the steam bath for a few minutes. Cool the solution slowly to room temperature. It may be necessary to scratch the inside of the test tube in order to induce crystallization. Cool the tube in ice, collect the product by suction filtration, and wash it with water followed by a small amount of cold methanol. Recrystallize the product from methanol, ethanol, or ethanol/ water. 

In further studies, Baker and Gaunt 4b, e) investigated the effect of the alcohol concentration on the triethylamine and pyridine-catalyzed reaction with phenyl isocyanate, and were able to confirm fully the validity of Equation (7) at 20° and 30° for methanol, ethanol, and isopropanol. The data are shown in Fig. 1. The intercept on the ordinate is the value h/kjcs while the slope of the line is equal to ki. From these values, kz/ki were calculated. 

Reviews. Hamersma and Snyder studied the effect of variation in reaction conditions in reductions with diimide generated from dipotassium azodicarboxylate. Air does not have a deleterious effect. Rate of reduction decreases with solvents in the following order pyridine > dioxane > dimethyl sulfoxide > methanol > ethanol > n-butanol, Water is a powerful inhibitor of the reaction in nonhydroxylic solvents but has practically no effect in hydroxylic solvents. 

Properties Amorphous solid. Mp 102-108C. Freely soluble in water, pyridine, acid solutions moderately soluble in methanol, ethanol, and acetone practically insoluble in benzene and halogenated hydrocarbons. 

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