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Acetone-//, solution

A) Toluene -sulphonates. For directions, using an acetone solution of toluene-/) Sulphonyl chloride, see p. 249 use o 3-o 5 g. of the phenol. Note that the chloride should be dissolved in a minimum of acetone, otherwise separation of the ester may be slow and incomplete. [Pg.340]

Z>) Toluene-p-sulphonylotion (p. 247). Proceed as in 3(a), but using 1 5 g of toluene-p-sulphonyl chloride, either finely pow dered or in concentrated acetone solution. Note. The sulphonyl derivative of a primary amine is soluble in aqueous sodium hydroxide, and the final solution must be diluted and acidified to precipitate the product. Recrystallise and take the m.p. (M.ps., pp. 550-551.)... [Pg.374]

Make a concentrated solution of anthracene in hot acetone. To about 2 ml. of this solution add a cold concentrated acetone solution of picric acid drop by drop, and note the formation of a red coloration which becomes deeper on further addition of the acid. If excess of picric acid is added, however, the solution becomes paler in colour, and this is to be avoided if possible. Boil to ensure that both components are in solution and then transfer to a small porcelain basin or watch-glass ruby-red crystals of anthracene picrate separate out on cooling. The product, however, is often contaminated with an excess of either anthracene or of picric acid, which appear as yellowish crystals. [Pg.394]

This substance (dA, I A) contains a free carboxyl group and is treated in warm acetone solution with an equimolecular quantity of the optically active base brucine (IB) upon cooling, the brucine salt (dA, IB) separates out first in a moderately pure condition, whilst the brucine salt (lA, IB) remains in solution ... [Pg.506]

Apply the test to compounds which contain chlorine or bromine. If the compound is a solid, dissolve 0 1 g. in the minimum volume of pure, dry acetone. To 1 ml. of the sodium iodide acetone reagent add 2 drops of the compound (if a hquid) or the acetone solution (if a sohd). Shake and allow to stand at room temperature for 3 minutes. Note whether a precipitate is formed and also whether the solution acquires a reddish-brown colour (liberation of iodine). If no change takes place at rocrm temperature, place the test-tube in a beaker of water at 50°. After 5 minutes, cool to room temperature, and observe whether a reaction has occurred. [Pg.1060]

The advantage of this method is that it avoids the use of hydrogen selenide, necessary for the preparation of selenourea from cyanamide (14). Benzoylselenourea is synthesized by the method of Douglass (24) by the action of potassium selenocyanate On benzoyl chloride in acetone solution. [Pg.229]

Alkyl-2-arylthiazoles and 4,5-disubstituted-2-(p-aminophenyl thiazoles were simflarly prepared from arylamides and a-halomethyl-ketones in alcoholic (239, 392, 641, 792) or acetonic solution (638, 651). [Pg.191]

By refluxing 54 and thioformamide for 16 hr m aqueous acetone solution, the expected compound 55 was obtained (Scheme 25). 55 in acetic medium, after treatment with hydrochloric add and zinc, gives 2-(4-thiazolyl)benziinida2ole derivatives 56 (554, 593). [Pg.198]

Fig. 41. The pervaporation separation of acetone—water mixtures achieved with a water-selective poly(vinyl alcohol) (PVA) membrane and with an acetone-selective siUcone mbber membrane. The PVA membrane is best suited to removing small amounts of water from a concentrated acetone solution, whereas the siUcone mbber membrane is best suited to removing small amounts of acetone from a dilute acetone stream (89). Fig. 41. The pervaporation separation of acetone—water mixtures achieved with a water-selective poly(vinyl alcohol) (PVA) membrane and with an acetone-selective siUcone mbber membrane. The PVA membrane is best suited to removing small amounts of water from a concentrated acetone solution, whereas the siUcone mbber membrane is best suited to removing small amounts of acetone from a dilute acetone stream (89).
In the mid-1980s a convenient and relatively safe procedure was developed for vacuum codistillation of dimethyldioxirane and acetone from acetone—caroate systems (107). The resulting acetone solution of dimethyldioxirane could be used in subsequent oxygenation reactions (92). [Pg.110]

Mixed aiihydiosulfides can be leaddy obtained by adding an acetone solution of the xanthate to an acetone solution of the acyl halide at —35 C (53) ... [Pg.364]

Milliliters of water required to start precipitation of the ester from 125 mL of an acetone solution of 0.1% concentration. [Pg.250]

Methyl chloride can be converted iato methyl iodide or bromide by refluxing ia acetone solution ia the presence of sodium iodide or bromide. The reactivity of methyl chloride and other aUphatic chlorides ia substitution reactions can often be iacteased by usiag a small amount of sodium or potassium iodide as ia the formation of methyl aryl ethers. Methyl chloride and potassium phthalimide do not readily react to give /V-methy1phtha1imide unless potassium iodide is added. The reaction to form methylceUulose and the Williamson synthesis to give methyl ethers are cataly2ed by small quantities of sodium or potassium iodide. [Pg.513]

Choline reineckate is used in the spectrophotometric determination of choline. Ammonium reineckate [13573-16-5] forms a water-insoluble complex with choline. The complex is soluble in acetone and a widely used method for determination of choline is by light absorption of acetone solutions... [Pg.101]

Chemical shifts in parentheses are for acetone solutions. Units are p.p.m. and Hz. [Pg.9]

Photodimers of IV-methylisoindole and isobenzofuran have been isolated [8+8] dimers are the major products. The [8 + 8] dimer (30) obtained by UV irradiation of an acetone solution of isobenzofuran at -60 °C has anti stereochemistry (78HCA444, 82CC1195). [Pg.42]

Analogously, pyrazolyl-aluminate and -indate ligands have been prepared <75JCS(D)749) and their chelating properties evaluated with cobalt, nickel, copper and zinc. Gallyl derivatives of pyrazoles and indazoles have been extensively studied by Storr and Trotter e.g. 75CJC2944) who determined several X-ray structures of these compounds. These derivatives exist in the solid state as dimers, such as (212) and (288). A NMR study in acetone solution showed the existence of a slow equilibrium between the dimer (212) and two identical tautomers (289) and (290) (Section 4.04.1.5.1) (81JOM(215)157). [Pg.236]

Commercial material contains up to 4% desmethylcolchicine. Purified by chromatography on alumina, eluting with CHCI3 [Ashley and Harris J Chem Soc 677 1944]. Alternatively, an acetone solution on alkali-free alumina has been used, and eluting with acetone [Nicholls and Tarbell J Am Chem Soc 75 1104 1953]. [Pg.522]

The reactor in Fig. 5 operates as follows. A feed solution containing a given concentration of pollutant is pumped to the adsorbent module at a fixed volumetric flow rate. The module is kept isothermal by a temperature control unit, such as a surrounding water bath. Finally, the concentration of the outlet solution is measured as a function of time from when the feed was introduced to the adsorbent module. These measurements are often plotted as breakthrough curves. Example breakthrough curves for an aqueous acetone solution flowing... [Pg.107]

Corrective Action Application TRW Corporation has developed one type of encapsulation system (U.S.EPA 1980). The TRW surface encapsulation requires that the waste material be thoroughly dried. The dried waste is stirred into an acetone solution of modified... [Pg.184]

A third form, w ooxyberberine (partial formula XII), was obtained by Pyman by the oxidation of berberineacetone (XIII) with permanganate in acetone solution. The steps in its formation are shown by... [Pg.334]

A 8 A solution of chromic acid is prepared by dissolving 26.72 g of chromium trioxide in a mixture of 23 ml of concentrated sulfuric acid and enough water to make the total volume of the solution 100 ml. Rapid dropwise addition of a slight excess of this reagent to an acetone solution (2 % or less) of the hydroxy steroid at room temperature or below with stirring usually results in complete conversion to ketone in less than 10 min. The product is isolated by dilution with water followed by filtration or extraction. [Pg.229]

The Bergmann variation of the Balz Schiemann reaction is a two-step process featuring copper- or copper halide-catalyzed decomposition of aqueous or acetone solutions of arenediazonium fluoroborates containing alkyl or halogen substituents [30] A recent modification is a one-step technique featuring simultaneous diazoti-zation and decomposition by addition of aqueous sodium nitrite at 25 °C to a mixture of fluorobonc acid, copper powder, and 2 isopropyl 6 methylaniline to give 2-isopropyl-6 methylfluorobenzene in 73% yield [37]... [Pg.275]

The thenyl chlorides appear to be more reactive in nucleophilic aliphatic substitution than the benzyl analogs. Thus, 2-thenyh chloride gives, in the reaction with sodium cyanide in ethanol, a mixture of ethyl 2-thenyl ether (25% yield) and 2-thenyl cyanide (32% yield), whereas benzyl chloride gives a high 3deld of benzyl cyanide uncontaminated with benzyl ether. When 2-thenyl chloride and benzyl chloride were allowed to compete for a deficiency of sodium amyloxide, 2-thenyl chloride reacted three times faster. In acetone solution 2-thenyl cyanide is obtained smoothl. ... [Pg.88]

Unsubstituted quinazoline 3-oxide was prepared in an attempt to react quinazoline with hydroxylamine. This reaction gave a product of variable composition, but when an acetone solution was heated in a sealed tube it gave quinazoline 3-oxide. The oxide is more conveniently prepared, in excellent yield, from o-aminobenzaldehyde oxime and ethyl orthoformate. This method appears to be of general use and has been used for the preparation of 4-methylquinazoline... [Pg.277]

Goi. As noted previously, an a-chlorine atom renders a ring-nitrogen atom very weakly basic. Cyanuric chloride (5) is a very weak base both because s-triazines are of low basicity and because each of the ring-nitrogen atoms is alpha to two chlorine atoms. Hence, this compound should be insensitive to acid catalysis or acid autocatalysis and this has been observed for the displacement of the first chlorine atom with alcohols in alcohol-acetone solution and with water (see, however. Section II,D,2,6). [Pg.298]

The stability of the heterocyclic ring toward oxidation by permanganate depends on the experimental conditions. In acid media the ring is not cleaved, and acetylisoxazoles are readily prepared from isopropenyl derivatives.2-Isoxazolines are dehydrogenated into isoxazoles (cf. 192 193). The stability of the heterocyclic ring is also observed when this oxidation is carried out in acetone solution. It is of interest that this method allows the preparation both of... [Pg.419]

The mixture is decanted into an Erlenmeyer flask, the residual green salts are washed with two 15-ml portions of acetone, and the washings are added to the main acetone solution. Cautiously, sodium bicarbonate (approx. 13 g) is added to the solution with swirling until the pH of the reaction mixture is neutral. The suspension is filtered, and the residue is washed with 10-15 ml of acetone. The filtrate is transferred to a round-bottom flask and concentrated on a rotary evaporator under an aspirator while the flask temperature is maintained at about 50°. The flask is cooled and the residue transferred to a separatory funnel, (If solidification occurs, the residue may be dissolved in ether to effect the transfer.) To the funnel is added 100 ml of saturated sodium chloride solution, and the mixture is extracted with two 50-ml portions of ether. The ether extracts are combined, washed with several 5-ml portions of water, dried over anhydrous magnesium sulfate, and filtered into a round-bottom flask. The ether may be distilled away at atmospheric pressure (steam bath) or evaporated on a rotary evaporator. On cooling, the residue should crystallize. If it does not, it may be treated with 5 ml of 30-60° petroleum ether, and crystallization may be induced by cooling and scratching. The crystalline product is collected by filtration and recrystallized from aqueous methanol. 4-r-Butylcyclohexanone has mp 48-49° (yield 60-90 %). [Pg.4]

The isopinene used in subsequent researches was obtained by fractionating the pinolene boiling at 144° to 145° C., a mixture of the o- and /3-isomeride, then treating it with hydrogen chloride and removing this acid by means of aniline. The hydrocarbon obtained was purified by oxidation with permanganate in acetone solution. It possesses the following constants —... [Pg.48]

They have also carried out the oxidation of selinene by means of ozone and potassium permanganate and have thus been able to establish that the regenerated selinene is not absolutely identical with the natural selinene. They are the first to record the existence of a hemi-cyclic-sesquiterpene this compound is termed pseudo-()3)-selinene. By passing a current of ozone into a solution of natural selinene (pseudo-( 8)-selinene). in acetic acid, there is obtained a diketone, CjjHogOj, which is purified by treatment with permanganate in acetone solution. Its properties are as. follows —... [Pg.90]


See other pages where Acetone-//, solution is mentioned: [Pg.86]    [Pg.528]    [Pg.54]    [Pg.242]    [Pg.451]    [Pg.300]    [Pg.76]    [Pg.367]    [Pg.165]    [Pg.623]    [Pg.54]    [Pg.570]    [Pg.637]    [Pg.414]    [Pg.687]    [Pg.299]    [Pg.272]    [Pg.184]    [Pg.359]    [Pg.289]    [Pg.530]   
See also in sourсe #XX -- [ Pg.27 ]




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