Acetone as a solvent

Now for some interesting features of the reaction, though they become fairly obvious with a little thought. First, the central methylene contains the more acidic protons (pATa 9) since it is flanked by two carbonyls, so the enolate anion formed involves this carbon (see Section 4.3.5). In other words, alkylation occurs on the central carbon of acetylacetone, not on the terminal carbons. Second, it is possible to use carbonyl compounds such as acetone as a solvent without these reacting under the reaction conditions. Acetone will have similar acidity (pATa 19) to the acetyl groups of acetylacetone, so likewise will not... 

The catalytic activities of all samples were tested for the liquid phase oxidation of 2,6-DTBP to quinone using H20, as an oxidant. Reactions were carried out under vigorous stirring in a two-neck glass flask equipped with a condenser and a thermometer. The oxidation of 2.6 DTBP was conducted using 10 mmol of substrate, 100 mg of catalyst, 10 g acetone as a solvent, and 30 mmol of 35 wt% H,02. The reaction was performed at 333 K for 2 h. The products were analyzed using a GC equipped with a HP-5 capillary column and a FID. 

For work in the sugar series, the advantage of acetone as a solvent (compared with water335 or ethanol, employed in the earlier studies mentioned) is that it dissolves the sodium iodide, the sulfonic ester, and the deoxyiodosugar derivative, but dissolves practically none of the sodium sulfonate formed. Use of other solvents is discussed on p. 197. 

In the presence of L-proline (20 mol%) as catalyst and acetone as a solvent (Scheme 5.15), the product (S)-34 was isolated in 86% yield and with excellent enantioselectivity (99% ee). When the reaction was carried out in (4 1) DMSO/ acetone solvent, yield and enantioselectivity decreased slightly (82% yield 95% ee). 

Used to introduce chromophores into amines in acetone as a solvent, with cesium bromide as a catalyst it is suggested that elevated temperatures (up to 80°C) are necessary for the complete derivatization of compounds containing diisopropylamines Reference 29... 

Shell first used acetone as a solvent, and then replaced it by acetonitrUe (1956). In this case, the process involves only a single extractive distillation, but includes intensive fractionation of the extract... 

Syntheses of alkyl phenyl ethers, C,H, OR, are carried out by refluxing aqueous or alcoholic solutions of alkali phenolates with alkyl halides the yields vary with the nature of the alkyl halides (40-80%). The reactive halogen in benzyl halides is easily replaced by an alkoxyl group (95%). ° The choice of a solvent is sometimes important. Thus, in the preparation of the alkyl ethers of o- and p-hydroxybiphenyl from a mixttire of the phenol, alkyl halide, and powdered potassium hydroxide, high yields are obtained using acetone as a solvent, whereas, with alcohol as solvent, only small yields are obtained. Triarylmethyl chlorides react with alcohols directly (97%). ... 

Chiral tridentate chromium(III) complexes catalyze highly enantio- and diastereo-selective hetero-Diels-Alder reaction between various aldehydes and dienes with one oxygen substituent (Sch. 60) [206]. Complex formation between catalysts and aldehydes could not be detected by IR and the successful use of acetone as a solvent casts doubt on a simple Lewis acid mechanism. 

Acetone as a Solvent. Acetone is an excellent solvent for cottonseed oU and for the antinutrients gossypol and aflatoxin. Acetone has found some commercial success in Sicily where Vaccarino used 96% aqueous acetone in a 50 ton/day batch process plant (162, 163). However, acetone has not had any other modern successes, probably because it produces a dark and hard-to-bleach cottonseed and because it imparts a disagreeable cat-like odor to the extracted meal. 

By the summer of 1915, the demand for acetone as a solvent for nitrocellulose in the manufacture of powder and dopes for airplane fabrics liecame so great that both sides began to look for substitutes for bromacetone, with the result that in July, 1915, the Germans introduced brom-... 

The attack of water upon the protonated ester during hydrolysis has been demonstrated with methyl acetate. By employing acetone as a solvent and having present only enough water to react with the ester,... 

Ruthenium tetroxide (RuOa) is also utilized for phenolic oxidation. Sodium 2,6-dichlorophenoxide (750) was oxidized with RuOa in H2O to afford 2,6-dichloro-p-benzoquinone (751) (60%), while the use of acetone as a solvent provided the corresponding biphenol 752 as the only isolatable product (20%) (Scheme 148). 

Furthermore the influence of acetone as a solvent was examined. For the homogeneously catalyzed epoxidation reaction in general, lower yields and selectivities are obtained with acetone as solvent. However for the transport of substrates and oxidant in and out of the zeolite channels, acetone could have a beneficial effect. This could not be confirmed by our experiments. 

Bernier gives the following advantages of the use of acetone as a solvent ... 

Berthon-Fabry et al. detected significant anisotropies in the SAXS pattern of carbon aerogels derived with acetone as a solvent and harsh synthesis conditions the anisotropy was found for q values <4 x 10 nm , while the scattering pattern revealed an isotropic structure at larger scattering vectors [41]. 

The full-scale test were performed to find the influence of reaction time, solvent nature, temperature, and reagents feed ration on intrinsic viscosity of polyarylate oximates to find out the optimal reaction conditions for their preparation in accordance with the Scheme 1. It was found that synthesis of polyarylate oximates can be carried out more efficiently in dioxane at 303 K during 40 min. with triethylamine as catalyst and molar ratio DKO/ (CAT) / (DCAIP) = 2/1/1. The reduced specific viscosity r red for a resulting polyarylate oximate was within the range of 0.71-0.81 dl/g. It should be noted that synthesis of polyarylate oximates from phenyl ketoximes in acetone as a solvent proceeded as a heterogeneous proeess and the resulting polymer precipitated from a solution. 

In 2011, a palladium-catalyzed ojyarylation of dihydronaphthalene and chromenes with o-iodophenols and its acetates was developed. The OTty-atylation of dihydronaphthalene, two electron-rich and one electron-poor chromenes with different o-iodophenols and their acetates has been investigated by using either Pd(OAc)2 (10 mol%) as a precatalyst and Ag2C03 as a base in acetone as a solvent or oxime palladacycle as a precatalyst and dicyclohejylamine as a base in DMA-H2O. The reactions, which were... 

The reaction of water with CH3CI in acetone as a solvent is represented by the equation... 

The solubility of fatty acids increases with an increase in the number of cis double bonds. This is illustrated in Fig. 3.3 with acetone as a solvent. The observed differences in solubility can be utilized for separation of saturated from unsaturated fatty acids. The mixture of acids is dissolved at room temperature and cooled stepwise to — 80 °C. However, the separation efficiency of such a fractional crystallization is limited since, for example, stearic acid is substantially more soluble in acetone containing oleic acid than in pure acetone. This mutual effect on solubility has not been considered in Fig. 3.3. 

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