Reaction Rubbing alcohol

Isopropyl alcohol is the main ingredient in rubbing alcohol It can decompose into acetone (the main ingredient in nail polish remover) and hydrogen gas according to the following reaction ... 

Three major non-polymer propylene derivatives are isopropanol, acetone, and acrylic acid. Isopropanol (isopropyl alcohol) is used mainly as a solvent. It has been made from propylene by reaction with sulfuric acid and water for at least the last 75 years, making its manufacture the oldest, still-running commercial organic chemical process. It is used in household rubbing alcohol because, unlike ethanol, it is unfit for human consumption even in small amounts. About 25 % of the isopropanol produced is used for making acetone, in competition with a route based on isopropylbenzene. 

Use the bond dissociation energies in Table 7.1 to calculate an approximate AH° (in kilojoules) for the industrial synthesis of isopropyl alcohol (rubbing alcohol) by reaction of water with propene, as shown at the top of the next column. 

The Friedel-Crafts alkylation is a classic illustration of the general class of electrophilic aromatic substitutions. Traditionally, Friedel-Crafts reactions require an alkyl halide as the electrophile source and at least a molar equivalent of aluminum chloride, a hygroscopic and caustic powder that is rather problematic to use in the introductory lab. An easy variant of this procedure utilizes the reactive substrate 1,4-dimethoxybenzene, /er butyl alcohol as the electrophile precursor, and sulfuric acid as the catalyst (72). We run this reaction on a microscale, and use commercial rubbing alcohol (70% aqueous 2-propanol) in place of methanol as the recystallization solvent. The product, l,4-di-7er/-butyl-2,5-dimethoxybenzene, exhibits simple and NMR, and... 

Before moving on here, there is a possible complication which must be addressed. This is the possibility that a tank of ammonia may only be putting out ammonia gas, rather than spewing liquid. This is no great hassle. In that case, the 3000 ml 3 necked flask is well packed in dry ice, and rubbing alcohol poured on the dry ice to create a very cold bath. When the ammonia gas hits the very cold flask, it will be condensed to a liquid. This may actually be a better procedure because it will assure that the ammonia does not have dissolved iron in it from the tank. Iron interferes with some lithium in ammonia reductions. I am not sure whether that is the case with this particular reaction. Input from serious experimenters is welcome. 

Consider some alcohols. Ethyl alcohol (drinking alcohol), methyl alcohol (wood alcohol), and isopropyl alcohol (rubbing alcohol) are quite different and yet remarkably the same in terms of the kinds of chemical reactions they undergo. The reactions all involve the -OH group on the molecule, the part of the molecule that really defines the identity of an alcohol, just as the double bond really defines the identity of an alkene. In many cases, it doesn t really matter what the rest of the molecule turns out to be. In reactions, one alcohol is pretty much the same as another. 

For alcohols of b.p. below 150°, mix 0- 5 g. of 3-nitrophthalic anhydride (Section VII,19) and 0-5 ml. (0-4 g.) of the dry alcohol in a test-tube fitted with a short condenser, and heat under reflux for 10 minutes after the mixture liquefies. For alcohols boiling above 150°, use the same quantities of reactants, add 5 ml. of dry toluene, heat under reflux until all the anhydride has dissolved and then for 20 minutes more remove the toluene under reduced pressure (suction with water pump). The reaction product usually solidifies upon cooling, particularly upon rubbing with a glass rod and standing. If it does not crystallise, extract it with dilute sodium bicarbonate solution, wash the extract with ether, and acidify. Recrystallise from hot water, or from 30 to 40 per cent, ethanol or from toluene. It may be noted that the m.p. of 3-nitrophthalic acid is 218°. 

One gram of 6,7-dihydro-5H-dibenz[c,e] azepine hydrochloride was dissolved in water, made alkaline with concentrated ammonia, and the resultant base extracted twice with benzene. The benzene layers were combined, dried with anhydrous potassium carbonate, and mixed with 0.261 g of allyl bromide at 25°-30°C. The reaction solution became turbid within a few minutes and showed a considerable crystalline deposit after standing 3 A days. The mixture was warmed VA hours on the steam bath in a loosely-stoppered flask, then cooled and filtered. The filtrate was washed twice with water and the benzene layer evaporated at diminished pressure. The liquid residue was dissolved in alcohol, shaken with charcoal and filtered. Addition to the filtrate of 0.3 gram of 85% phosphoric acid in alcohol gave a clear solution which, when seeded and rubbed, yielded 6-allyl-6,7-dihydro-5H-dlbenz[c,e] azepine phosphate, MP about 211°-215°C with decomposition. 

Experiment.—Azoxybenzenefromphenylhydroxylamine and nitrosobenzene.-—Phenylhydroxylamine (1 g.) is added to a solution of 1 g. of nitrosobenzene in 10 c.c. of alcohol. The mixture is shaken while a few drops of concentrated potassium hydroxide solution (1 1) are added, and is then warmed on the water bath for a few minutes. The yellowish-red solution thus formed deposits yellow crystals of the reaction-product when cooled and rubbed with a glass rod. Since azoxybenzene melts at 36°, it has a great tendency to separate from a supersaturated solution in the form of an oil. By recrystallisation from a little alcohol or from petrol ether (retain a few crystals for inoculation) the compound is obtained as a pale yellow or almost colourless solid. 

Special cases of solid lubrication arc boundary anil IIP (extreme pressure) lubrication In both cases ihe solid lubricant is formed by chemical reaction of special compounds, usually applied as oil solutions, with the metallic rubbing surfaces Typical boundary lubricants are the fatty acids which react with the metal surface to form metallic soaps which then carry the load. Strongly adsorbed hut nonreacting substances of linear structure, such as long chain tally alcohols, can also act as boundary lubricants but only under very mild conditions... 

Dissolve a small quantity of crystallised phenol (about gramme) in s c.c. of water in a test-tube and add c.c. of benzoyl chloride make the solution alkaline with a solution of caustic soda and, with shaking, heat gently a short time over a free flame. If the reaction-mixture is cooled by water and then shaken and the sides of the tube rubbed with a glass rod, the oil separating out solidifies to colourless crystals, which are filtered off with suction, washed with water, pressed out on a porous plate, and recrystallised in a small test-tube from a little alcohoL Melting-point, 68-69°. 

For the preparation of mannose, mannitol (50 g) was dissolved in a little water and treated with ferrous sulfate (12.5 g) in aqueous solution and then with 5-6% hydrogen peroxide (150 ml). At the end of the reaction the mixture was treated with an excess of freshly precipitated barium carbonate, filtered, much concentrated at 50°/30 mm, and finally evaporated to a syrup in a vacuum. The syrup was treated with 10 times its volume of anhydrous ethanol, then filtered, and an excess of ether was added. The resulting colorless flocks collected to form a pale yellow syrup, which partly crystallized when rubbed with alcohol and ether. The yield was not given the identity of the product with mannose was proved by conversion into the phenylhydrazone. 

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