Ethyl alcohol, reaction with oxygen atoms

Constitution. Pelletierine behaves as a secondary amine and the oxygen atom of the alkaloid is present in the form of an aldehyde group, since the base yields an oxime, convertible by the action of phosphorus pentachloride into a nitrile, b.p. 104-6°/13 mm., which is hydrolysed by caustic potash in alcohol to an acid, the ethyl ester of which is Loffler and Kaim s ethyl -2-piperidylpropionate. Pelletierine is not directly oxidisable to this acid. It also yields a liquid hydrazone, b.p. 130°/20 ram., which with sodium in alcohol at 136-70° reduces to dZ-eoniine. These reactions are explained by the following formulas, in which pelletierine is represented as -2-piperidylpropionaldehyde. 

An ester is an organic compound formed from the condensation reaction between a carboxylic acid and an alcohol. A water molecule is eliminated as the oxygen atom of the alcohol links to the carbon atom of the carbonyl group. For example, ethanol reacts with acetic acid to give ethyl acetate ... 

By a similar mechanism to that proposed for the formation of ethyl ether by dehydration of ethanol, it is possible that the reaction occurs stepwise with the intermediate dehydration of one ethanol molecule to form ethylene which then reacts with another ethanol molecule to form butanol. It is thus possible that higher alcohols may be built up by the reaction of olefins with the lower alcohols. Mixed oxide type of catalysts are used in the process of a nature similar to those which have been found effective in alcohol synthesis from hydrogen and carbon monoxide. It should lie noted here that catalysts which promote the union of carbon atoms must be used, and since potassium oxide promoted catalysts composed of mixtures of zinc, copper, or chromium oxides have been found to be effective in the syuthesis of higher alcohols, such catalysts should be useful in promoting the addition of olefins to alcohols or other oxygenated organic molecules.77... 

Zinc alkides form addition-products with aldehydes and ketones, which on treatment with water, yield secondary and tertiary alcohols, respectively. In the reactions between organo-metallic compounds and substances which contain the carbonyl group (C = 0), the positive, metallic atom enters into combination with the negative oxygen atom, and the alkyl radical unites with carbon. The structure of the compound formed from zinc ethyl and acetyl chloride is an example —... 

Certain derivatives of benzamide tend to confirm this view. When the silver salt of benzamide is treated with ethyl iodide, the metal is replaced by the alkyl radical. The product formed is determined by the temperature at which reaction takes place. The substance obtained at room-temperature yields ammonia and has the formula given below. It belongs to the class of compounds known as iminoesters, which may be considered as derived from esters by the replacement of the oxygen atom of the carbonyl group by the bivalent imino group, =NH. Like esters it yields an alcohol on hydrolysis at the same time the imino group is replaced by oxygen. 

A sulfonate ester can also be prepared by the reaction of an alcohol and a sulfonic acid under acidic conditions, exactly analogous to the same reaction with a carboxylic acid. In the presence of an acid catalyst, 2-methylpropane-sulfonic acid (181) reacts with ethanol to give ethyl 2-methylpropanesulfonate (187). The mechanism of this reaction is remarkably similar to that for the reaction of a carboxylic acid and an alcohol in the presence of an acid catalyst (see Section 20.5.2). The reaction proceeds by initial reaction of 181 with H+ to give 182. The oxygen of ethanol is the electron-donating species in this reaction, and the most electrophilic atom is sulfur, so reaction of 182 and ethanol generates a new S-O bond in 183. 

The solvent used in these dimerization reactions dictates the activity of the catalyst. Besides benzene and dioxane, acetic acid [246,247], halogenated hydrocarbons [245,247], nitroderivatives [247], sulfones, tetrahydrofuran (THF), ethyl acetate, phenol, dimethylformamide, hydroquinone, catechol, benzyl alcohol, salicylic acid, anisole, and acetone have been used [247]. In solvents like benzene and chlorohydrocarbons and in highly polar solvents like dimethylsulfoxide and dimethylformamide, dimerization does not occur. The reaction proceeds in solvents containing oxygen atoms. The dissociative solvents like phenol and acetic acid show high solvent effect. In carboxylic acids the rate of dimerization decreases with an increase in pK . 

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