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Magnesium saturation pressure

K, respectively. The solubility of mercury in magnesium has been determined by measuring the saturated pressure of mercury vapour above the alloys under conditions of non-equilibrium solidification. The solubility increases from 0.71% at 298 K to 0.93% at 721 K. The pressures were used to determine the activity of mercury in the alloys. The activity was characterized by a net concentration independence in the heterogeneous region (Mg-l-MgaHg), but in the solid-solution region the activity increased monotonically with mercury con-... [Pg.42]

In a 500 ml. three-necked flask, equipped with a thermometer, a sealed Hershberg stirrer and a reflux condenser, place 32-5 g. of phosphoric oxide and add 115-5 g. (67-5 ml.) of 85 per cent, orthophosphoric acid (1). When the stirred mixture has cooled to room temperature, introduce 166 g. of potassium iodide and 22-5 g. of redistilled 1 4-butanediol (b.p. 228-230° or 133-135°/18 mm.). Heat the mixture with stirring at 100-120° for 4 hours. Cool the stirred mixture to room temperature and add 75 ml. of water and 125 ml. of ether. Separate the ethereal layer, decolourise it by shaking with 25 ml. of 10 per cent, sodium thiosulphate solution, wash with 100 ml. of cold, saturated sodium chloride solution, and dry with anhydrous magnesium sulphate. Remove the ether by flash distillation (Section 11,13 compare Fig. II, 13, 4) on a steam bath and distil the residue from a Claisen flask with fractionating side arm under diminished pressure. Collect the 1 4-diiodobutane at 110°/6 mm. the yield is 65 g. [Pg.284]

Place 100 g. of adipic acid in a 750 ml. round-bottomed flask and add successively 100 g. (127 ml.) of absolute ethyl alcohol, 250 ml. of sodium-dried benzene and 40 g. (22 ml.) of concentrated sulphuric acid (the last-named cautiously and with gentle swirling of the contents of the flask). Attach a reflux condenser and reflux the mixture gently for 5-6 hours. Pour the reaction mixture into excess of water (2-3 volumes), separate the benzene layer (1), wash it with saturated sodium bicarbonate solution until eflfervescence ceases, then with water, and dry with anhydrous magnesium or calcium sulphate. Remove most of the benzene by distillation under normal pressure until the temperature rises to 100° using the apparatus of Fig. II, 13, 4 but substituting a 250 ml. Claisen flask for the distilling flask then distil under reduced pressure and collect the ethyl adipate at 134-135°/17 mm. The yield is 130 g. [Pg.386]

Method B. Reflux a mixture of 101 g. of sebacic acid, 196 g. (248 ml.) of absolute ethjd alcohol and 20 ml. of concentrated sulphuric acid for 12 hours. Distil oft about half of the alcohol on a water bath dilute the residue with 500-750 ml. of water, remove the upper layer of crude ester, and extract the aqueous layer with ether. Wash the combined ethereal extract and crude ester with water, then with saturated sodium bicarbonate solution until effervescence ceases, and finally with water. Dry with anhydrous magnesium or sodium sulphate, remove the ether on a water bath, and distil the residue under reduced pressure. B.p. 155-157°/6 mm. Yield llOg. [Pg.387]

Dissolve the solid in 700 ml. of water in a 1500 ml. round-bottomed flask, and add a solution of 88 ml. of concentrated sulphuric acid in about 200 ml. of water until the liquid has a distinct odour of sulphur dioxide sufficient heat will be liberated in the neutralisation to cause the solution to boil. Immediately steam distil the liquid (Fig. II, 40, 1 it is better to use the apparatus shown in Fig. II, 41, 3) until a sample of the distillate gives only a slight precipitate with bromine water. About 700 ml. of distillate should be collected. Saturate the steam distillate with salt, extract the dl with ether, dry the extract with a little anhydrous magnesium or calcium sulphate, distil oflF the ether (compare Fig. II, 13, 4, but with a 50 ml. Claisen flask replacing the distilling flask) and distil the residue under diminished pressure. Collect the p-cresol at 95-96°/15 mm. the colourless liquid solidifies to a white crystalline solid, m.p. 31°. The yield is 24 g. [Pg.667]

In a 250 ml. conical flask mix a solution of 14 g. of sodium hydroxide in 40 ml. of water and 21 g. (20 ml.) of pure benzaldehyde (Section IV,115). Add 15 g. of hydroxylamine hydrochloride in small portions, and shake the mixture continually (mechanical stirring may be employed with advantage). Some heat is developed and the benzaldehyde eventually disappears. Upon coohiig, a crystalline mass of the sodium derivative separates out. Add sufficient water to form a clear solution, and pass carbon dioxide into the solution until saturated. A colourless emulsion of the a or syn-aldoxime separates. Extract the oxime with ether, dry the extract over anhydrous magnesium or sodium sulphate, and remove the ether on a water bath. Distil the residue under diminished pressure (Fig. 11,20, 1). Collect the pure syn-benzaldoxime (a-benzald-oxime) at 122-124°/12 mm. this gradually solidifies on cooling in ice and melts at 35°. The yield is 12 g. [Pg.719]

This product is sufficiently pure for the preparation of phenylacetic acid and its ethyl ester, but it contains some benzyl tso-cyanide and usually develops an appreciable colour on standing. The following procedure removes the iso-cyanide and gives a stable water-white compound. Shake the once-distilled benzyl cyanide vigorously for 5 minutes with an equal volume of warm (60°) 60 per cent, sulphuric acid (prepared by adding 55 ml. of concentrated sulphuric acid to 100 ml. of water). Separate the benzyl cyanide, wash it with an equal volume of sa+urated sodium bicarbonate solution and then with an equal volume of half-saturated sodium chloride solution- Dry with anhydrous magnesium sulphate and distil under reduced pressure. The loss in washing is very small (compare n-Butyl Cyanide, Section 111,113, in which concentrated hydrochloric acid is employed). [Pg.761]

The purified commercial di-n-butyl d-tartrate, m.p. 22°, may be used. It may be prepared by using the procedure described under i o-propyl lactate (Section 111,102). Place a mixture of 75 g. of d-tartaric acid, 10 g. of Zeo-Karb 225/H, 110 g. (136 ml.) of redistilled n-butyl alcohol and 150 ml. of sodium-dried benzene in a 1-litre three-necked flask equipped with a mercury-sealed stirrer, a double surface condenser and an automatic water separator (see Fig. Ill, 126,1). Reflux the mixture with stirring for 10 hours about 21 ml. of water collect in the water separator. FUter off the ion-exchange resin at the pump and wash it with two 30-40 ml. portions of hot benzene. Wash the combined filtrate and washings with two 75 ml. portions of saturated sodium bicarbonate solution, followed by lOu ml. of water, and dry over anhydrous magnesium sulphate. Remove the benzene by distillation under reduced pressure (water pump) and finally distil the residue. Collect the di-n-butyl d-tartrate at 150°/1 5 mm. The yield is 90 g. [Pg.952]

After vigorous shaking the layers were separated and three extractions of the agueous layer with diethyl ether were carried out. The combined solutions were washed twice with saturated NaCl solution and then dried over magnesium sulfate. The greater part of the solvents was distilled off at normal pressure through a... [Pg.234]

A mixture consisting of 0.69 g (10.5 mmoles) of zinc-copper couple, 12 ml of dry ether, and a small crystal of iodine, is stirred with a magnetic stirrer and 2.34 g (0.7 ml, 8.75 mmoles) of methylene iodide is added. The mixture is warmed with an infrared lamp to initiate the reaction which is allowed to proceed for 30 min in a water bath at 35°. A solution of 0.97 g (2.5 mmoles) of cholest-4-en-3/ -ol in 7 ml of dry ether is added over a period of 20 min, and the mixture is stirred for an additional hr at 40°. The reaction mixture is cooled with an ice bath and diluted with a saturated solution of magnesium chloride. The supernatant is decanted from the precipitate, and the precipitate is washed twice with ether. The combined ether extracts are washed with saturated sodium chloride solution and dried over anhydrous sodium sulfate. The solvent is removed under reduced pressure and the residue is chromatographed immediately on 50 g of alumina (activity III). Elution with benzene gives 0.62 g (62%) of crystalline 4/5,5/5-methylene-5 -cholestan-3/5-ol. Recrystallization from acetone gives material of mp 94-95° Hd -10°. [Pg.112]

A-Homo-estra- Q>),2,Aa-triene-4, l-dione (45) from the l-ketal mono-dibromocarbene adduct (43b). A solution of monoadduct 17-ketal (43b 0.46 g) and dry pyridine (20 ml) is heated at reflux for 2 hr. After cooling the reaction mixture, the pyridine hydrobromide (0.1 g) is removed by filtration and the filtrate is concentrated under reduced pressure. The resultant gum is dissolved in ether and washed successively with water, ice-cold 4 N hydrochloric acid, water, 5% aqueous sodium bicarbonate solution, water, saturated salt solution and dried over anhydrous magnesium sulfate. Evaporation of the solvent at reduced pressure gives 3-bromo-4-methoxy-A-homo-estra-2,4,5(10)-trien-17-one (44 0.22 g) mp 158-162° after crystallization from ether. [Pg.371]

Bromo-4-methoxy-A-homo-estra-2,4,5(10)-trien-17-one (44 0. 2g), is dissolved in formic acid, 2 ml of boron trifluoride etherate is added and the mixture is stirred vigorously at 0° for 2 hr. A brown mass ca. 0.12 g) is obtained after evaporation of the solvents at reduced pressure. This material is diluted with water and extracted with chloroform. The chloroform extracts are washed successively with water and saturated salt solution, dried over anhydrous magnesium sulfate and evaporated at reduced pressure to give 95 mg of a product which is purified by filtration through a column of neutral alumina and crystallization of the residue after evaporation of the solvent from ethyl acetate-petroleum ether. The resulting A-homo-estra-l(10),2,4a-triene-4,17-dione (45), mp 143-146°, is identical to the tropone (45) prepared from monoadduct 17-ketone (43a). [Pg.371]

A-Homo-estra-, 4, )-triene-3, l-dione (50). A solution of bromo ketone (49 0.2 g), silver perchlorate (0.5 g) and 20% aqueous acetone (30 ml) is heated at reflux with stirring for 30 min and then allowed to cool to room temperature. The mixture is filtered to remove precipitated silver bromide (ca. 0.19 g) and the filtrate is diluted with water (200 ml) and then extracted with chloroform. The chloroform extracts are washed, successively with water, 5% sodium bicarbonate solution, water and saturated salt solution. After being dried over anhydrous magnesium sulfate, the solvents are removed at reduced pressure to give a solid. Recrystallization from ethyl acetate gives A-homo-estra-l,4,5(10)-triene-3,17-dione (50 0.17 g) mp 193-197°. [Pg.373]

A solution of cholestane-5a,6a-diol 6-tosylate (115a, 0.15 g) in dimethylformamide (20 ml) containing calcium carbonate (0.2 g) is heated for 8 hr on a steam bath. The reaction mixture is then cooled, filtered and diluted with water. The mixture is extracted with ether and the ether extracts are washed with water and saturated salt solution, dried over anhydrous magnesium sulfate and evaporated to dryness under reduced pressure to give the A-homo-B-norketone (116a, 85 mg) mp 123-125° [a]j> 21° (CHCI3). [Pg.394]

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]

To a suspension of 25.0 g of 11/3,17a,21-trihydroxy-6,16a-dimethyl-4,6-pregnadiene-3,20-dione in 1.5 liters of alcohol-free chloroform cooled to about 5°C in an ice bath is added with constant stirring 750 ml of cold, concentrated hydrochloric acid and then 750 ml of formalin (low in methanol). The mixture is removed from the ice bath and stirred at room temperature for 7 hours. The layers are separated and the aqueous phase is back-extracted twice with chloroform. The combined organic layers are washed twice with a 5% solution of sodium bicarbonate, and twice with a saturated salt solution. The solution is dried over magnesium sulfate and evaporated to dryness under reduced pressure. [Pg.391]

The lower glycol layer was separated and washed with benzene. The benzene layer and the benzene washings were combined and the combined solution was divided into two equal portions, one of which was used for the isolation of 17a-hydroxyprogesterone 3,20-bis-(ethylene ketal) as follows. The benzene solution was washed with 5% sodium carbonate solution, water and saturated sodium chloride solution. After being dried over anhydrous magnesium sulfate the solution was concentrated to dryness at reduced pressure. [Pg.915]

The upper layer was neutralized by the addition of cold 10% sodium hydroxide solution while stirring in an ice bath. The rate of addition of the sodium hydroxide was regulated to keep the temperature below 10°C. The benzene extracts from the peracid layer were combined and washed with cold 10% sodium hydroxide solution and with saturated sodium chloride solution. All the aqueous layers were washed again with the same portion of benzene. The combined benzene layers were dried over anhydrous magnesium sulfate and concentrated to dryness at reduced pressure. [Pg.915]


See other pages where Magnesium saturation pressure is mentioned: [Pg.252]    [Pg.478]    [Pg.478]    [Pg.540]    [Pg.572]    [Pg.669]    [Pg.765]    [Pg.860]    [Pg.940]    [Pg.975]    [Pg.37]    [Pg.179]    [Pg.187]    [Pg.222]    [Pg.9]    [Pg.52]    [Pg.52]    [Pg.126]    [Pg.66]    [Pg.115]    [Pg.115]    [Pg.41]    [Pg.77]    [Pg.472]    [Pg.472]    [Pg.472]    [Pg.394]    [Pg.396]    [Pg.404]    [Pg.404]    [Pg.20]    [Pg.90]    [Pg.98]   
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Saturation pressure

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