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Time, drying, water reducible

Recrystd aniline was dropped slowly into an aqueous soln of recrystd oxalic acid. Aniline oxalate was filtered off, washed several times with water and recrystd three times from 95% EtOH. Treatment with satd Na2C03 soln, regenerated aniline which was distd from the soln, dried and redistd under reduced pressure [Knowles Ind Eng Chem 12 881 7920]. [Pg.113]

Acetylene and Potassium in Liquid Ammonia Potassium (40 g) is dissolved in 1 liter of dry liquid ammonia. Dry acetylene is then bubbled into the solution until the blue color is discharged. A solution of 15 g of estrone in 300 ml of dioxane is prepared and diluted with 300 ml of ether, cooled, and added to the potassium acetylide solution over a period of 10 min. The liquid ammonia is allowed to evaporate, an additional 500 ml of ether is added, and the mixture is allowed to stand overnight. About 3 liters of 5 % sulfuric acid is added and the organic layer separated. The water layer is re-extracted with fresh ether, and the combined ether extracts are washed twice with 5 % sodium carbonate solution, th6n several times with water, and finally evaporated under reduced pressure. The residue is dissolved in 150 ml of methanol, then an equal quantity of hot water is added and the mixture cooled. The precipitated solid is collected, washed with cold 60 % methanol and crystallized once from methanol-water to give 14.8 g (85%) of 17a-ethynylestradiol mp 143-144°. [Pg.137]

In a 100-ml flask is placed a mixture of 19.5 g (0.18 mole) of freshly sublimed, pulverized selenium dioxide, 15 g (0.10 mole) of df/-camphor and 15 ml of acetic anhydride. The flask is fitted with a magnetic stirrer and a condenser, and the mixture is heated to 135° on an oil bath with stirring for 16 hours. After cooling, the mixture is diluted with ether to precipitate selenium, which is then filtered off, and the volatile materials are removed under reduced pressure. The residue is dissolved in ether (200 ml), washed four times with 50-ml portions of water and then washed several times with saturated sodium bicarbonate solution (until the washes are basic). The ether solution is finally washed several times with water, then dried, and the ether is evaporated. The residue may be purified by sublimation at reduced pressure or recrystallized from aqueous ethanol (with clarification by Norit, if necessary). The product is yellow, mp 197-199°. [Pg.16]

Carbethoxycyclooctanone (40 g, 0.2 mole) dissolved in 50 ml of dry benzene is added to the stirred sodium hydride over about 30 minutes at room temperature. The mixture is stirred an additional hour at room temperature to complete the formation of the sodium salt. Methyl iodide (284 g, 2.0 mole, a 10-fold excess) is added to the stirred solution over 1 hour and the stirring at room temperature is continued for 20-24 hours. The reaction mixture is poured cautiously into 500 ml of 3 aqueous acetic acid, and the aqueous solution is extracted three times with 100-ml portions of benzene. The combined benzene extracts are washed three times with water and dried over anhydrous magnesium sulfate. Benzene and excess methyl iodide are removed under reduced pressure (rotary evaporator) and the residue is distilled. [Pg.101]

To circumvent these difficulties, a preparation of water-soluble coelenterazine has been developed (Teranishi and Shimomura, 1997a). The preparation contains coelenterazine and 50-times (by weight) of hydroxypropyl-P-cyclodextrin. To prepare this material, 0.1 ml of 3.0 mM coelenterazine in methanol and 0.2 ml of 45 mM solution of the cyclodextrin are mixed and dried under reduced pressure. The dried residue is extracted with 1.0 ml of lOmM phosphate buffer, pH 7.0, containing 2 mM EDTA (if needed), and the extract (after centrifugation) is again dried under reduced pressure. With this preparation, an aqueous solution containing up to 3 mM coelenterazine can be made. [Pg.167]

A mixture of 1.44 g. (0.0099 mole) of indole-3-carboxaldehyde,2 7.0 g. (0.053 mole) of diammonium hydrogen phosphate, 30 g. (30 ml., 0.34 mole) of 1-nitropropane, and 10 ml. of glacial acetic acid is refluxed for 12.5 hours. During the reflux period the pale-yellow mixture becomes dark red. The volatile reactants and solvent are removed under reduced pressure, and an excess of water is then added to the dark residue. After a short time, crude indole-3-carbonitrile precipitates rapidly. It is separated by filtration and dried under reduced pressure weight 1.20-1.34 g. (85-95%). Crystallization from acetone-hexane, with decoloriza-tion by activated carbon, yields 0.68-0.89 g. (48-63%) of fairly pure indole-3-carbonitrile, m.p. 179.5-182.5° (Note 1). [Pg.58]

Synthesis in m-cresol. The dianhydride (1.35 mmol) is added to a stirred solution of 1.35 mmol of die diamine in die appropriate amount of m-cresol containing 6 drops of isoquinoline under N2 at room temperature. After 3 h, it is heated to reflux (ca. 200° C) and maintained at that temperature for 3 h. During this time, the water of imidization is distilled from die reaction mixture along with 1 to 3 mL of m-cresol. The m-cresol is continually replaced to keep the total volume of the solution constant. After die solution is allowed to cool to room temperature, it is diluted witii 20 mL of m-cresol and then slowly added to 1 L of vigorously stirred 95% ethanol. The precipitated polymer is collected by filtration, washed witii ethanol and ether and dried under reduced pressure at 125°C for 24 h. [Pg.294]

Transfer the soil extract (from Section 6.1) into a 1000-mL separatory funnel, add 200 mL of water and 10 mL of saturated sodium chloride solution, and extract the sample with 100 mL of dichloromethane three times. Dry the dichloromethane extract with anhydrous sodium sulfate in a funnel in a similar manner as described for juice, pulp and rind, and collect the dried solution in a 500-mL round-bottom flask. Evaporate the dichloromethane under reduced pressure. Dissolve the residue in 3 mL of benzene. [Pg.1291]

The organic layer is separated and washed twice with a total of 200 mL of water. The aqueous reaction layer is extracted five times with a total of 600 mL of chloroform. The organic extracts are washed twice with a total amount of 250 mL of water. The combined organic layers are dried with magnesium sulfate and evaporated to dryness. The residual solid product is carefully dried under reduced pressure to yield 48-50 g (2 100%) (Note 8). [Pg.173]

The creamy suspension is allowed to cool to room temperature, and the electrodes of a pH meter are inserted (Note 4). A solution of 20.5 g. (0.15 mole) of zinc chloride (Note 5) in 75 ml. of water is added dropwise with vigorous stirring over a period of 45 minutes, while the pH is maintained at 7 by the simultaneous dropwise addition of a 4A aqueous solution of sodium hydroxide (Note 6). The mixture is stirred for 1 hour and is then filtered with suction the solid product is dried under reduced pressure over phosphorus pentoxide. The dry material is slurried with 200 ml. of petroleum ether (b.p. 30-60°), and the solvent is decanted. This process is repeated five times, and the combined extract is evaporated at reduced pressure. The yield of almost pure -chlorophenyl isothiocyanate, obtained as a readily crystallizing oil with a pleasant anise-like odor, is 33-35 g. (65-68%), m.p. 44-45°. The product can be recrystallized from the minimum amount of ethanol at 50°. [Pg.11]

At the end of the 24-hour period, the ethanol is removed under reduced pressure on a steam bath. A 2N sulfuric acid solution (2 1.) is added to the warm residue, and the mixture is stirred vigorously for 3—4 hours (Note 3). The solid is removed by suction filtration and washed several times with water. The air-dried product is a pale-bufi powder weighing 180-190 g., m.p. 126-128°. The solid is added to 1.5 1. of ethyl acetate, the mix-... [Pg.77]

A 250 mL, three-necked, round-bottomed flask equipped with a mechanical stirrer and a reflux condenser was charged with glacial acetic acid (173 mL), benzil (27.0 g, 0.129 mol), ammonium acetate (67.7 g, 0.87 mol) and cyclohexanone (13.5mL, 0.133 mol). The mixture was stirred and refluxed for 1.5h and then poured into 450 mL of ice-cold and vigorously stirred water while hot. The mixture was slowly cooled to ambient temperature and left overnight. The resulting solid was collected by filtration, washed four times with 50 mL of water, crushed in a mortar and dried under reduced pressure to give the imidazole as a yellowish-green solid (35.8 g, 97.3 % yield). [Pg.137]

The moist cake is scraped from the flask and allowed to dry in a 16-in. porcelain evaporating dish until the odor of hydrochloric acid is faint (about 24 hours, but this time can be reduced to about 8 hours if a gentle stream of air is directed onto the solid). The solid material is returned to the dried flask and mixed thoroughly with about 200 ml. of water. Two liters of acetone is added, and the mixture is boiled under reflux for 15 minutes, then cooled to room temperature and filtered through a 6-in. Buchner funnel. The solid on the filter is returned to the flask, treated with 100 ml. of water, and extracted with 1 1. of boiling acetone as before... [Pg.104]

To a flask equipped with a stirrer condenser with a drying tube is added 25 ml (0.274 mole) of n-butanol followed by 1.0 gm (0.0435 mole) of sodium metal. After the sodium has reacted, 8.9 gm (0.04 mole) of di-p-tolylcarbodiimide in 15 ml of ether is added rapidly. The mixture becomes warm and after 15 min it is diluted with ether, washed three times with water, dried, and the ether removed under reduced pressure. The residue is a viscous oil which crystallizes on prolonged suction to give 11.8 gm (100%). [Pg.93]


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