Mole Of Alcohol Research Articles

Condensation of acetylenic acetals with ketones

A study was made of the reaction of propargylaldehyde acetal with a number of ketones under the influence of BF3 etherate. With acetone and methyl ethyl ketone the reaction goes with the cleavage of 1 mole of alcohol and the formation of the corresponding ethoxyacetylenic ketones.

Heats of mixing. V. Systems of n-alcohols with n-hexane

Heats of mixing have been measured at 25�, 35�, and 45� for mixtures of ethanol, propan-1-ol, butan-1-ol, hexan-1-ol, and octan-1-ol with n-hexane and for methanol with n-hexane at 45�. These heats of mixing were found to increase with an increase in temperature and to decrease with an increase in the size of the alcohol molecule. They showed anomalies for the systems containing methanol and ethanol. An explanation of these anomalies has been given. The contribution of the hydroxyl groups to the enthalpy of any mixture of a n-alcohol with a n-alkane is defined as the enthalpy change on replacing the alcohol by its homomorphic alkane. The experimental results given here are consistent with the postulate that the contribution of the hydroxyl groups (per mole of alcohol) to the enthalpy depends only on the ratio of the number of hydroxyl groups to that of hydrocarbon units in the mixture. This postulate, if generally true, can be used for the prediction of the heats of mixing of any n-alcohol with a n-alkane and of the enthalpy difference between any n-alcohol and its liquid homomorphic alkane. Other data support the conclusion that the postulate holds for all concentrations of alcohol, but show that the analogous postulate applied to free energies holds only for infinitely dilute solutions of alcohols. The interaction of the hydroxyl groups with the hydrocarbon units contribute -7.8 and -4.5 kJ/mole of alcohol to the enthalpies and free energies respectively of these infinitely dilute solutions. The required values of the heats of mixing of the lower alkanes with n-hexane were estimated from the enthalpies of the alkanes using the principle of congruence; these were found to be appreciable and negative. They are in sign agreement with values extrapolated, from measured data at a higher temperature, using a principle of corresponding states for chain molecules.

The Synthesis and the Cleavage Reactions of Hexaalkyldisiloxanes

Synthesis of hexaalkyldisiloxane in good yield was made by treating a product of reaction between silicon tetrachloride and 2-2.5 moles of alcohol, without refining, with RMgX in excess and hydrolysis of the product. This method was more simple than the Sommer's method of using ethyl orthosilicate as a starting material and higher yield was obtainable. It is known that trimethylethoxysilane reacts easily with CH3MgBr or CH3MgCl and yields tetramethylsilane, but the reaction of CH3MgI and trimethylethoxysilane was found to proceeded with extreme difficulty in the writer's experiment.Also, the synthesis of triethylchlorosilane was made by passing in hydrogen chloride gas into a sulfuric acid solution of hexaethyldisiloxane. This method however, was not applicable in the synthesis of trimethylchlorosilane.

Reactions of orthoesters of titanium. III. Reactions of Ethyl and Isopropyl Titanates with α‐hydroxy carboxylic acids

AbstractStepwise replacement of alkyl groups of ethyl and isopropyl titanates by acyl groups of lactic, mandelic, and salicylic acids has been investigated by taking the reactants in predetermined stoichiometric proportions and causing them to react in refluxing benzene. The number of alkyl groups replaced was determined by estimating the alcohol liberated in the reaction and by analysing the reaction product. When the alkyl titanates are acted upon by 2 moles of these acids, salicylic acid liberates 4 moles of alcohol (per mole alkyl titanate) whereas remaining two acids displace only 3 or 3.5 moles of alcohol. Thus di‐lactate and mandelate derivatives appear to withhold very firmly the remaining alkoxy group. However, with 3 moles (or higher proportions) of these acids, alkyl titanates yield, in every case, an equimolecular mixture of di‐ and tri‐acylates. The lactate and mandelate products are white solids, but the salicylates are orange or deep red in colour. Mono‐lactate, salicylate and mandelate derivatives are soluble in benzene, whereas the equimolecular mixture of di‐ and tri‐lactate dissolves in water without precipitation of titanium hydroxide.

SYNTHESIS OF 2,4-THIAZOLIDINEDIONE-2-AZINES AND 2,4-THIAZOLIDINEDIONE-2-DIMETHYLHYDRAZONES FROM THIOCYANOESTERS AND HYDRAZINES

Thiocyanoesters were prepared from 2-bromoesters and potassium thiocyanate, and a series of substituted thiazolidinedione-2-azines was obtained from these thiocyanoesters using hydrazine hydrate. The structure of the thiazolidinedione-2-azines was determined by hydrolysis using hydrochloric acid in ethanol. The reaction of thiocyanoesters with dimethylhydrazine, generally speaking, was analogous to their reaction with hydrazine, but there were many differences. Only 1 mole of alcohol was eliminated rather than 2, and there was no apparent reaction for the ethyl 2-thiocyanononanoate and the methyl phenylthiocyanoacetate. Furthermore, the reaction of methyl 2-thiocyanoisobutyrate with dimethylhydrazine did not give a 2,4-thiazolidinedione-2-dimethylhydrazone but rather an addition product, N-dimethylamino-S-(1-methyl-1-carbomethoxy) ethylisothiourea. To illustrate the reactivity of the thiocyano group, benzyl thiocyanate was treated with hydrazine and the product was found to be dibenzyldisulphide, and ammonia was evolved. Similarly, trimethylene dithiocyanate gave the dimer of trimethylene disulphide. Finally, benzyl thiocyanate formed an addition product with dimethylhydrazine which was N-dimethylamino-S-benzylthiourea.

Titanium salts of mono‐carboxylic acids. I. Attempted Preparation of Titanium Tetra‐Soaps

AbstractWith a view to prepare the tetra‐soaps of titanium, the reaction between titanium alkoxides and excess of various fatty acids has been studied in refluxing benzene. The alcohol produced was removed azeotropically with the solvent. However, all the four alkoxy groups per titanium atom could not be replaced in any of the experiments. Even on carrying out the reaction in a higher boiling solvent like toluene, similar results were obtained and only 3 moles of alcohol per mole of the alkoxide could be azeotropically distilled out. It has been shown that the fourth alkoxy group is held in such a manner that it cannot be displaced even on refluxing the reaction product with higher alcohols or water. On heating the product to about 200° under reduced pressure, the excess fatty acid which distilled out has been shown to be mixed with some ester and the residue was found to be a decomposed titanium soap of the type TiOx(OOCR)4−2x with the value of ‘x’ nearly 0.5. These observations have been explained either by the steric hindrance to the entry of the fourth acid group or by the occurrence of other side reactions with the formation of organic ester.

The preparation of peroxides by the oxidation of propane

AbstractThe following is a description of an investigation into the optimum conditions for the preparation of peroxides by incomplete oxidation of propane. Special attention has been paid to the optimum formation of hydrogen peroxide.In connection with the removal of heat, it is probably only possible to use a 90/10 propane‐oxygen mixture in a technical apparatus. With this mixture the optimum production of hydrogen peroxide was found at an average reaction temperature of 465°C and a contact time of 4 sec.Under these conditions 15 moles of peroxides (9 moles of which was free hydrogen peroxide) was formed per 100 moles of propane used. At the same time 83 moles of propene was formed, in addition to 87 moles of water, 34 moles of carbon oxides, 12 moles of aldehydes, 1 mole of alcohol and 1 mole of hydrogen.