Overheating alcohol

Large-scale preparation by addition of fert-butanol to chromium trioxide in a full unstirred flask with poor cooling detonated owing to local overheating. Effective cooling and stirring are essential [1]. It may safely be prepared by addition of a 40% aqueous solution of chromium trioxide to the alcohol [2],... 

In the presence of sodium benzylate two molecules of benzal-dehyde react with the alcoholate to form an addition product. When the reaction mixture is overheated an important side... 

The causes of variations in yield by the use of the okler methods can now be explained. When benzaldehyde is added to the alcoholate, and especially when the latter is still warm, local overheating results in fact, the temperature may rise far above xoo° with the result that benzyl ether is formed. Simultaneously, the sodium benzylate is converted into sodium benzoate, which is of no value for inducing the desired reaction, and consequently very little benzyl benzoate is obtained. The same side reactions explain the failure of this experiment when the benzyl alcohol used in preparing the catalyst (sodium benzylate) is contaminated with benzaldehyde. 

The need for great care to avoid the possibility of detonation of perchloryl compounds by exposure to shock, overheating or sparks is stressed. The compounds are generally more sensitive to impact than mercury fulminate and are of comparable sensitivity to lead azide [1], A range of highly explosive alkyl perchlorates [2] and perchlorylamines [3] have been prepared by interaction of dichlorine heptaoxide with alcohols or amines in carbon tetrachloride solution. The solutions of the products were not sensitive to mechanical shock and could... 

When alcohols such as t-butyl alcohol, t-amyl alcohol, t-hexyl alcohol, were dissolved in fluorosulphonic acid-antimony pentafluoride solutions diluted with sulphur dioxide (in order to achieve better mixing of the less viscous solutions and to avoid the possibility of local overheating) at temperatures ranging around — 60°, stable, slightly coloured solutions... 

Caution. DMEAA is air-sensitive and inflames upon contact with water. All the reactions are performed under an inert atmosphere. In the synthesis of DMEAA, it is crucial to remove all the aluminum particles from the reaction solution by filtration after the reaction is complete. The aluminum particles remaining from the incomplete filtration can cause autocatalytic and exothermic gas-evolving decomposition of DMEAA which may lead to an explosion. Also, the product should not be overheated during the vacuum distillation. For disposal, DMEAA should be diluted with heptane and allowed to react slowly with isopropyl alcohol with cooling in a fume hood. 

Test Solution Transfer an accurately weighed amount of sample, equivalent to about 200 mg of a-tocopherol, into a 250-mL round-bottom, glass-stoppered flask dissolve it in 50 mL of absolute alcohol and reflux for 1 min. While the solution is boiling, add 1 g of potassium hydroxide pellets, one at a time to avoid overheating, through the condenser. 

If 2-methylfuran is to be made intentionally, it was found that the reaction temperature should be 250 °C (instead of 135 °C for furfuryl alcohol), and that the copper chromite catalyst should be mixed with activated charcoal [110]. As the reaction is highly exothermic, good care must be exercised to prevent an inactivation of the catalyst by overheating. 

The supernatant layer of alcohol prevents the reactants dropping directly onto the sodium ethoxide and causing local overheating. 

Crystals Dr eryst powder slight acetic odor sensitive to light. Poison d 3.2S. mp 178-180° (overheating results in decompn). One g dissolves in 2.5 ml cold, 1 ml boiling water sol in alcohol. Keep well closed and protected from light. Aq solns decomp on standing, yielding a yellow ppt. 

Oily, strongly fuming liquid. Vigorously attacks cork, rubber and other organic substances. M.p. 1.8°C, b.p. 113.5°C. Explosive if United or overheated, especially in the presence of air. Miscible with water and alcohols. Only slightly soluble in other solvents. 

Properties Wh. cryst. powd. si. acetic odor sol. in alcohol, water m.w. 318.68 dens. 3.2544 m.p. 178-180 C (overheating causes decomp.) Toxicology ACGIH TLV/TWA 0.01 mg(Hg)/m (skin) LD50 (oral, rat) 40,900 pg/kg, (skin, rat) 570 mg/kg, (IP, mouse) 6500 pg/kg toxic by ing., inh., IV, IP, subcut. routes mod. toxic by skin contact strong irritant experimental teratogen, reproductive effects TSCA listed Hazardous Decomp. Prods. Heated to decomp.. 

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