Aldehyde-Free Alcohol

Alcohol, Aldehyde-Free Dissolve 2.5 g of lead acetate in 5 mL of water, add the solution to 1000 mL of alcohol contained in a glass-stoppered bottle, and mix. Dissolve 5 g of potassium hydroxide in 25 mL of warm alcohol, cool, and add slowly, without stirring, to the alcoholic solution of lead acetate. Allow to stand for 1 h, then shake the mixture vigorously, allow to stand overnight, decant the clear liquid, and recover the alcohol by distillation. Ethyl Alcohol FCC, Alcohol USP, or USSD 3A or 30 may be used. If the titration of a 250-mL sample of the alcohol by Hydroxylamine Hydrochloride TS does not exceed 0.25 mL of 0.5 N alcoholic potassium hydroxide, the above treatment may be omitted. 

Alcohol, Aldehyde-Free, 849 Alcohol, Anhydrous, 849 Alcohol, Dehydrated, 849 Alcohol, Diluted, 849 Alcohol, 70%, 849 Alcohol, 80%, 849 Alcohol, 90%, 849 Alcohol C-6, 506, (S3)76 Alcohol C-8, 542 Alcohol C-9, 540 Alcohol C-10,476 Alcohol C-l 1,562 Alcohol C-12,518... 

Semicarbazones. Dissolve 1 g. of semicarbazide hydrochloride and 1 5g. of crystallised sodium acetate in 8-10 ml. of water add 0 - 5-1 g. of the aldehyde or ketone and shake. If the mixture is turbid, add alcohol (acetone-free) or water until a clear solution is obtained shake the mixture for a few minutes and allow to stand. Usually the semicarbazone crystallises from the cold solution on standing, the time varying from a few minutes to several hours. The reaction may be accelerated,... 

Packer and Richardson (1975) and Packer et al. (1980) made use of the fact that electrons can be generated in water by y-radiation from a 60Co source (Scheme 8-29) to induce a free radical chain reaction between diazonium ions and alcohols, aldehydes, or formate ion. It has to be emphasized that the radiolytically formed solvated electron in Scheme 8-29 is only a part of the initiation steps (Scheme 8-30) by which an aryl radical is formed. The aryl radical initiates the propagation steps shown in Scheme 8-31. Here the alcohol, aldehyde, or formate ion (RH2) is the reducing agent (i.e., the electron donor) for the main reaction. The process is a hydro-de-diazoniation. 

Using dicyclohexyl-18-crown-6 it is possible to dissolve potassium hydroxide in benzene at a concentration which exceeds 0.15 mol dm-3 (Pedersen, 1967). The free OH- has been shown to be an excellent reagent for ester hydrolysis under such conditions. The related solubilization of potassium permanganate in benzene, to yield purple benzene , enables oxidations to be performed in this solvent (Hiraoka, 1982). Thus, it is possible to oxidize a range of alkenes, alcohols, aldehydes, and alkylbenzenes under mild conditions using this solubilized reagent. For example, purple benzene will oxidize many alkenes or alcohols virtually instantaneously at room temperature to yield the corresponding carboxylic acids in near-quantitative yields (Sam Simmons, 1972). 

In real systems (hydrocarbon-02-catalyst), various oxidation products, such as alcohols, aldehydes, ketones, bifunctional compounds, are formed in the course of oxidation. Many of them readily react with ion-oxidants in oxidative reactions. Therefore, radicals are generated via several routes in the developed oxidative process, and the ratio of rates of these processes changes with the development of the process [5], The products of hydrocarbon oxidation interact with the catalyst and change the ligand sphere around the transition metal ion. This phenomenon was studied for the decomposition of sec-decyl hydroperoxide to free radicals catalyzed by cupric stearate in the presence of alcohol, ketone, and carbon acid [70-74], The addition of all these compounds was found to lower the effective rate constant of catalytic hydroperoxide decomposition. The experimental data are in agreement with the following scheme of the parallel equilibrium reactions with the formation of Cu-hydroperoxide complexes with a lower activity. 

The ruthenium carbene catalysts 1 developed by Grubbs are distinguished by an exceptional tolerance towards polar functional groups [3]. Although generalizations are difficult and further experimental data are necessary in order to obtain a fully comprehensive picture, some trends may be deduced from the literature reports. Thus, many examples indicate that ethers, silyl ethers, acetals, esters, amides, carbamates, sulfonamides, silanes and various heterocyclic entities do not disturb. Moreover, ketones and even aldehyde functions are compatible, in contrast to reactions catalyzed by the molybdenum alkylidene complex 24 which is known to react with these groups under certain conditions [26]. Even unprotected alcohols and free carboxylic acids seem to be tolerated by 1. It should also be emphasized that the sensitivity of 1 toward the substitution pattern of alkenes outlined above usually leaves pre-existing di-, tri- and tetrasubstituted double bonds in the substrates unaffected. A nice example that illustrates many of these features is the clean dimerization of FK-506 45 to compound 46 reported by Schreiber et al. (Scheme 12) [27]. 

Experiment 5. Angeli-Rimini Reaction.—A few drops of an aldehyde (any of those prepared) are dissolved in aldehyde-free 1 alcohol and about the same amount of benzene sulphohydroxamic acid (for the preparation of which see p. 192) is added in the case of aliphatic substances, twice as much of the acid is used. To this mixture, kept cool and shaken, 2 A-sodium hydroxide is added, in an amount judged to be about two molecular proportions. After standing for fifteen minutes the alkaline mixture is made just acid to Congo red and finally a drop of ferric chloride solution is added. An intense red colour is produced. 

Complete reduction of acyl chlorides to primary alcohols is not nearly as important as the reduction to aldehydes since alcohols are readily obtained by reduction of more accessible compounds such as aldehydes, free carboxylic acids or their esters [83,968]. Because aldehydes are the primary products of the reduction of acyl chlorides strong reducing agents convert acyl chlorides directly to alcohols. 

Surface lipids of plants. The thick cuticle (Fig. 1-6) that covers the outer surfaces of green plants consists largely of waxes and other lipids but also contains a complex polymeric matrix of cutin (stems and leaves) or suberin (roots and wound surfaces).135/135a Plant waxes commonly have C10 - C30 chains in both acid and alcohol components. Methyl branches are frequently present. A major function of the waxes is to inhibit evaporation of water and to protect the outer cell layer. In addition, the methyl branched components may inhibit enzymatic breakdown by microbes. Free fatty acids, free alcohols, aldehydes, ketones, 13-dike tones, and alkanes are also present in plant surface waxes. Chain lengths are usually C20 - C35.136 Hydrocarbon formation can occur in other parts of a plant as well as in the cuticle. Thus, normal heptane constitutes up to 98% of the volatile portion of the turpentine of Pin us jeffreyi.81... 

Figure 14.15 illustrates a third advanced procedure for the alcohol —> aldehyde oxidation with the example of a racemization-free oxidation of an enantiomerically pure alcohol. Two oxidizing agents are employed, a stoichiometric amount of NaOCl... 

Saponifying Solution Dissolve 40 g of potassium hydroxide in about 900 mL of aldehyde-free alcohol maintained at a temperature of 15° until solution is complete. Warm to room temperature, and add sufficient aldehyde-free alcohol to make 1000 mL. 

Hydroxylamine Hydrochloride Solution Dissolve 50 g of hydroxylamine hydrochloride (preferably reagent grade or freshly recrystallized before using) in 90 mL of water, and dilute to 1000 mL with aldehyde-free alcohol. Adjust the solution to a pH of 3.4 with 0.5 N alcoholic potassium hydroxide. 

Potassium Hydroxide, 0.5 N, Alcoholic (Caution The solution may become very hot. Allow it to cool before adding the aldehyde-free alcohol.) Dissolve about 35 g of potassium hydroxide (KOH) in 20 mL of water, and add sufficient aldehyde-free alcohol to make 1000 mL. Allow the solution to stand in a tightly stoppered bottle for 24 h. Then quickly decant the clear supernatant liquid into a suitable, tight container, and standardize as follows Transfer quantitatively 25 mL of 0.5 N hydrochloric acid into a flask, dilute with 50 mL of water, add 2 drops of Phenolphthalein TS, and titrate with the alcoholic potassium hydroxide solution until a permanent, pale pink color is produced. Calculate the normality. Store this solution in tightly stoppered bottles protected from light. 

Alcoholic Sulfuric Acid, 0.5 N, 859 Alcoholic Sulfuric Acid, 5 N, 859 Alcohols, Total, 815 ALDC Activity, (S3)110 Aldehyde C-6, 504 Aldehyde C-7, 502, (S3)76 Aldehyde C-8, 540 Aldehyde C-9, 538 Aldehyde C-10, 476 Aldehyde C-ll Undecyclic, 560 Aldehyde C-ll Undecylenic, 560 Aldehyde C-12,518 Aldehyde C-12 MNA, 534 Aldehyde C-14 Pure, So-Called, 560 Aldehyde C-16, 492 Aldehyde C-18, So-Called, 538 Aldehyde-Free Alcohol, 849 Aldehydes and Ketones, 816 Hydroxylamine Method, 816 Hydroxylamine/Tert-Butyl Alcohol Method, 816... 

---