Acetone acetals

Suspend 0 25 g. of 2 4-dinitrophenylhydrazine in 5 ml. of methanol and add 0-4 0-5 ml. of concentrated sulphuric acid cautiously. FUter the warm solution and add a solution of 0 1-0-2 g. of the carbonyl compound in a small volume of methanol or of ether. If no sohd separate within 10 minutes, dUute the solution carefuUy with 2N sulphuric acid. CoUect the solid by suction filtration and wash it with a little methanol. RecrystaUise the derivative from alcohol, dUute alcohol, alcohol with ethyl acetate or chloroform or acetone, acetic acid, dioxan, nitromethane, nitrobenzene or xylene. 

Glycohc acid is soluble ia water, methanol, ethanol, acetone, acetic acid, and ethyl acetate. It is slightly soluble ia ethyl ether and spatingly soluble ia hydrocarbon solvents. 

N,N-D1methylformam1de from Carlo Erba Chemicals, from Fluka AG, or from Merck 4 Company, Inc. was used as received. Other solvents (for example, acetone, acetic acid, acetonitrile) can also be used. 

Ethanol Methanol Dioxane Acetone Acetic acid Formic acid ... 

Besides acetophenone, this reaction was also applied to p-chloro- andp-methoxyacetophenone, and even to an aliphatic ketone, acetone (although the yield was stated to be only half as large as that obtained from mesityl oxide, i.e., less than 30%, Dorofeenko and co-workers reported a 45% yield of 2,4,6-trimethylpyrylium perchlorate from acetone, acetic anhydride, and perchloric acid), and is the standard method for preparing pyrylium salts with identical substituents in positions 2 and 4. The acylating agent may be an anhydride in the presence of anhydrous or hydrated ferric chloride, or of boron fluoride, or the acid chloride with ferric chloride.Schneider and co-workers ... 

In another approach to the meso problem , utilization of a chiral auxiliary attached at nitrogen appears to induce very high stereoselectivity. Reduction of the optically active imide 10a (see Appendix) with tetramethylammonium triacetoxyborohydridc in acetone/ acetic acid at 25 "C gives a 4 96 mixture of the diastcreomers 11a and 12a in 87% yield44. On changing the solvent to acetonitrile/acetic acid the diastereomeric ratio is improved to < 1 99, but the yield is lower (63%). 

Thin layer chromatography of (-)-DAG on Silica Gel G using the solvent system, benzene methanol acetone acetic acid (70 20 5 5), shows one spot with Rf 0.7. 

Monflier et al. (1997) have suggested Pd catalysed hydrocarboxylation of higher alpha olefins in which chemically modified P-cyclodextrin (especially dimethyl P-cyclodextrin) is u.sed in water in preference to a co-solvent like methanol, acetone, acetic acid, acetonitrile, etc. Here, quantitative recycling of the aqueous phase is possible due to easy phase separation without emulsions. A similar strategy has been adopted by Monflier et al. (1998) for biphasic hydrogenations for water-in.soluble aldehydes like undecenal using a water-soluble Ru/triphenylphosphine trisulphonate complex with a. suitably modified p-cyclodextrin. 

There are some other mixtures that are predominantly aliphatic that are associated with stinker beans. These contain extraordinarily increased amounts of methanol, ethanol, acetone, acetic acid, 2-butanediol, butanols, 2,3-pentanedione, 3-pentanone, and butane.25... 

York, R. and Holmes, R. C. (1942) Ind. Eng. Chem. 34, 345. Vapor-liquid equilibria of the system acetone-acetic acid-water. 

Equilibrium data for the system acetone-acetic acid, at 760 mmHg, mol... 

Generally, primary aliphatic alcohols are oxidized to their respective aldehydes, secondary aliphatic and aromatic alcohols to the corresponding ketones, and allyl and benzyl alcohols to their carboxylic acid or carboxylate ions. For instance, 2-propanol, acetaldehyde, and methyl-benzoate ions are oxidized quantitatively to acetone, acetate, and terephtalate ion respectively, while toluene is converted into benzoate ion with an 86% yield. Controlling the number of coulombs passed through the solution allows oxidation in good yield of benzyl alcohol to its aldehyde. For diols,502 some excellent selectivity has been reached by changing the experimental conditions such as pH, number of coulombs, and temperature. 

The use of a nitrogen nucleophile in the side chain (as an amide) also leads to an intramolecular 1,4-addition under the standard conditions for the palladium-catalyzed 1,4-oxidation reactions52. Nitrogen nucleophiles employed for this reaction comprise tosy-lamides, carboxamides, carbamates and ureas. The reactions are run in acetone-acetic acid with p-benzoquinone (BQ) as the oxidant. In most cases highly stereo- and regioselective reactions were obtained and some examples are given in Table 3. 

Two-dimensional techniques are usually employed if both phospho-glycerides and glycolipids are present, but it is possible to resolve members of both classes using a diisobutylketone-acetic acid-water mixture (40 25 5). A solvent composed of acetone, acetic acid and water (100 2 1) will separate the mono- and di-galactosyldiglycerides, which are particularly abundant in plant extracts, from phosphoglycerides, which remain at the origin. 

Silylated primary allylic amines, e.g. CH2=CHCH2N(SiMe3)2, are produced from allylic chlorides and the mixed reagent AgI/LiN(SiMe3)2205. The formation of allylic amines from olefins by the ene reaction is shown in equation 77. The ene adducts 205 from bis(2,2,2-trichloroethyl) azodicarboxylate are converted into 206 by zinc dust in acetone/acetic acid206. 

Kansiz et al. has published a paper wherein they used MIR and sequential injections to monitor an acetone-butanol fermentation process.17 In this work, acetone, acetate, n-butanol, butyrate, and glucose were analyzed automatically, using computer-controlled sampling techniques. In this case, gas chromatography was the reference method. The SEPs for the components were acetone, 0.077 acetate, 0.063 butyrate, 0.058 -butanol, 0.301 and glucose, 0.493 g/1. The authors state that the precision and accuracy of the MIR methods were as good as the reference method. 

Soluble in acetone, acetic acid, alcohol (Weast, 1986), glycols, and fat solvents (Windholz et al,... 

Treatment of 1 with chromium trioxide or chromic acid in a mixture of acetone, acetic acid, and acetic anhydride at — 60°C produces a mixture of 2 and iV -demethylvinblastine (55) (71). When this crude mixture is treated with formic acid in acetic anhydride, 2 is obtained in 50-70% yield based on starting vinblastine. A modification of this procedure involves the use of preformed chromic acid with either tetrahydrofuran or ethyl acetate as solvent. Using these methods, yields of 2 as high as 90% have been obtained (72). 

Simple organic molecules Ethanol Butanol Acetone Acetic acid Lactic acid Saccharomyces cerevisiae Pachysolen tamiophilus, some Clostridium spp. Clostridium acetobutylicum, C. saccharoacetobutylicum Clostridium acetobutylicum, C. saccharoacetobutylicum Various acetic acid bacteria Lactobacillus spp. 

Hexamethylenetetramine, Citric acid. Hydrogen peroxide Nitric acid. Phosphorus pentoxide, Solex Nitric acid. Ammonium nitrate. Paraformaldehyde, Hexamine, Acetone, Acetic acid. Acetic anhydride Diethanolethylamine, Thionly chloride. Chloroform, Acetone, Sodium carbonate... 

The substance is also soluble in concentrated hydrochloric acid, acetone, acetic acid, nitrobenzene, aniline, pyridine, and nitroglycerine, at room temperature. In water its solubility is only 0.08% at 25°C. 

Benzoic acid exists in the monomeric form in solution in acetone, acetic acid, ethyl ether, ethyl alcohol, ethyl acetate, and phenol in these solutions the single molecules are stabilized by hydrogen-bond formation with the solvent. 

Nitrocellulose will dissolve in many solvents, e.g. acetone, acetic esters, ether-alcohol. There also exist types of nitrocellulose soluble in ethyl alcohol alone. 

Irradiation of compound 357 (R = Me) in methanol and ethanol at 300 nm gave ethyl 2-methyl-4-oxo-4//-pyrimido[2,l-a]isoquinoline-3-car-boxylate (371) and 3-alkoxy-2-methyl 4//-pyrimido[2,l-a]isoquinoline-4-ones (369, R = Me, R1 = Me, Et) along with two imidazo[2,l-a]isoquino-lines (368, R = Me and 372) and a ring-opened product (92AJC1811). At 254 nm the yields of 4//-pyrimido[2,l-a]isoquinolin-4-ones (369, R = Me and 371) and 368, (R = Me) were lower no formation or trace of them was observed in acetonitrile, acetone, acetic acid, and ethyl acetate. Irradition of compound 357 (R = Me) at 300 nm in acetonitrile containing 36% hydrochloric acid afforded 3-chloro-2-methyl-4//-pyrimido[2,l-a]isoquinolin-4-one (373) in 31-81% yields and other products. 

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