Acetone as solvent

There are two commercial solvent crystaUi2ation processes. The Emersol Process, patented in 1942 by Emery Industries, uses methanol as solvent and the Armour-Texaco Process, patented in 1948, uses acetone as solvent. The fatty acids to be separated are dissolved in the solvent and cooled, usually in a double-pipe chiller. Internal scrapers rotating at low rpm remove the crystals from the chilled surface. The slurry is then separated by means of a rotary vacuum filter. The filter cake is sprayed with cold solvent to remove free Hquid acids, and the solvents are removed by flash evaporation and steam stripping and recovered for reuse (10). 

Oxepin has also been converted photochemically to phenol in 74% yield. This reaction occurs under irradiation conditions by which benzene oxide is excited to a triplet state, e.g. by irradiation in acetone as solvent.207 A rare example for a nucleophilic catalysis of the aromatization of an oxepin/benzene oxide to a phenol has been reported for /err-butyl oxepin-4-carboxylate which undergoes a rearrangement reaction in the presence of trimethylamine to give a mixture of /m-butyl 3-hydroxybenzoate (94%) and 4-hydroxybenzoate (6%).243... 

Since the benzene emission in the thermal decomposition of benzoyl peroxide results from radical transfer by the phenyl component of a benzoyloxy-phenyl radical pair, phenyl benzoate produced by radical combination within the same pair should appear in absorption. A weak transient absorption has been tentatively ascribed to the ester (Lehnig and Fischer, 1970) but the complexity of the spectrum and short relaxation time (Fischer, personal communication) makes unambiguous assignment difficult. Using 4-chlorobenzoyl peroxide in hexachloro-acetone as solvent, however, the simpler spectrum of 4-chlorophenyl 4-chlorobenzoate is clearly seen as enhanced absorption, together with... 

Thiobenzamides can also be obtained by reaction of N-thiobenzoyl-1,2,4-triazole (D) or N-thiobenzoylbenzotriazole (E) and amines (in cyclohexane, CHC13, or acetone as solvents, at temperatures between 10 and 50 °C),[166] as indicated in Table 4-6. 

Reaction is terminated at the desired monoaddition-stage by using free guanidine (base), and acetone as solvent (376, 377). Guanidine salts and carbodiimides in dimethylformamide, in spite of the presence of excess of the former, yield 1,2,6-trisubstituted isomelamines (XLIII), presmnably by loss of arylamine from the intermediate labile triguanide (XLII) (375). 

These composite data strongly suggest that the presence of adventitious water or other hydrogen donors can markedly affect the observed rate of epoxidation. For example, Murray and Gu have reported AH = 5.0 kcalmol" for the DMDO epoxidation of cyclohexene in CDCI3 and 7.4 kcalmol" in acetone as solvent . Curci and coworkers also reported an a value of 9.3 kcalmol" for the DMDO epoxidation of isobutylene in acetone . These barriers are significantly lower than the 13-18 kcalmoD gas-phase barriers reported " at the B3LYP level of theory (Tables 3 and 4). Activation barriers of 12.6,... 

The oxidation of n-octane and the epoxidation of 1-hexene were performed in a 25 ml Parr reactor using 30% aqueous H2O2 as an oxidant and acetone as solvent at 100 °C and 80 °C, respectively and stirred at 500 RPM. Prior to product analysis, the product mixtures were diluted with acetone in order to obtain a single liquid-phase. The products were analyzed on a HP 5890 Series II GC equipped with a 25 m long HP-FFAP (polar) capillary column. 

Since these are chemical equilibriiun reactions, by modifying the reaction conditions, i.e., using acetone as solvent instead of isopropanol, the reaction can be reversed, and therefore used for the oxidation (dehydrogenation) of alcohols (Oppenauer-type oxidation) [43]. Moreover, since acetone is the hy-... 

Use Method 106.1 of MIL-STD-650 with.acetone as solvent Weigh ca 50g of die expl to within 10mg, place in a 400-ml beaker and add 100ml of acetone. Heat on a steam bath until all lumps are broken and all soluble material is dissolved. Pour die mixture thru... 

The mutual solubility Of two salts.—Numerous investigations have been made on this subject in the light of the phase rule by H. W. B. Roozeboom 8 and others. C. E. Linebarger also submitted mixtures of two salts to the action of various organic liquids in which one of the salts was insoluble. If both salts passed into soln. in a molecular ratio, it was assumed that a double salt is formed in soln. With a mixture of sodium and mercuric chlorides no double salt was formed with benzene or acetone as solvent, but with acetic ether, a salt, (HgCl2)2NaCl, was formed similarly also with lithium and mercuric chlorides, the salt HgCl2.LiCl was formed but no double salt was observed with potassium and mercuric chlorides in the same solvent. 

Synthesis (Pohland, 1953 1955 1963 janssen and Karel (Janssen)1956 Sullivan et al., 1963) In the Grignard reaction of 3-dimethylamino-2-methyl-1-phenyl-propan-lone with benzylmagnesium chloride 4-dimethylamino-3-methyl-1,2-diphenyl-butan-2-ol is formed. The preferred product is the a-diastereomer(75 % a-form, 15 % p-form). The a-form crystallizes and the diastereomeric p-form remains in solution, because of its better solubility. Racemic resolution to obtain the analgetically (+) enantiomer can be achieved on the pure a-Grignard product via fractional crystallization of the salts with D-camphorsulfonic acid. Alternatively the resolution can be achieved by treating the racemic mannich product 3-dimethylamino-2-methyl-1-phenyl-propan-1-one with (-)-dibenzoyltartaric acid in acetone as solvent. 

Reaction conditions 10 mmol 2,6-DTBP, 30 mmol H,02(35wt% in aqueous solution), 100 mg catalyst, 10 g acetone (as solvent), 337 K, 2 h. 

Az = absorbance measurement at wavelength z These equations are designed for the use of 100% acetone as solvent. Practical Aspects of the Experiment... 

Oxyfunctionalization reactions of n-alkanes are carried out at room temperature and atmospheric pressure with t.BHP as oxidans and acetone as solvent. Product analysis was done with GC on a 50 m CP Sil-88 capillary column from Chrompack. 

Entropy is the driving force for transacetulization, and equilibrium is shifted further toward the product by the use of acetone as solvent... 

Orthoesters are hydrolyzed on contact with DDQ via a mechanism in which apparently the acidity of the DDQ hydroquinone plays no role. Interestingly, it is possible either to hydrolyze an orthoester in the presence of an unsaturated alcohol, using wet acetone as solvent, or oxidize an unsaturated alcohol in the presence of an orthoester, employing anhydrous benzene as solvent.128... 

Allylic oxidation of a variety of cyclic alkenes with copper complexes of different pybox ligands (8) and with various peresters shows high enantioselectivity (80-96% ee). Use of phenylhydrazine as an additive and acetone as solvent accelerates the reaction. It has been suggested that the phenylhydrazone is responsible for the observed acceleration. Using EPR spectra, it has been shown that the Cu(II) species is reduced to Cu(I) by phenylhydrazine and phenylhydrazone. It has been found that the presence of a gem-diphenyl group at C(5) and a secondary or tertiary alkyl substituent at the chiral centre at C(4) of the oxazoline rings is crucial for high enantioselectivity. 

Used for the precolumn preparation of fluorescent derivatives of carboxylic acids using acetone as solvent and with crown ether and alkali as catalysts Reference 5... 

The Sn2 reaction of the tosylate ester with acetate ion in acetone as solvent produced an ester with [a] = —0.83. (Again, the configuration of the product cannot be determined solely on the basis of this experiment.)... 

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