Reduced pressure drying

Fractionally distd under reduced pressure. Dried with sodium and again fractionally distd or refluxed with boric anhydride and distd (b 195-205°/5mm), the distillate being neutralised with NaOH and again fractionally distd. Also purified by distn from Raney nickel and by preparative GLC. 

The mixture of alcohols is placed in a 1000-mL round-bottomed flask, dissolved in 300 mL of ether, and cooled to 0°C. To this solution is added via an addition funnel over a 30-min period a mixture of sodium dichromate dihydrate (27.5 g, 0.092 mol), 100 mL of water, and 10.2 mL of coned sulfuric acid. The mixture is stirred at 0°C for 1 hr, warmed to room temperature where stirring is maintained overnight, diluted with 200 mL of water, and poured into a separatory funnel. The layers are separated and the aqueous phase is extracted with ether (3 x 200 mL). The combined organic layers are washed with saturated sodium bicarbonate solution (200 mL) and brine (200 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated by rotary evaporation to give 16.8-17.8 g (61-65%) of verbenone (Note 7). Final purification is achieved by distillation of the oil through a 5-in Vigreux column at reduced pressure (dry ice-acetone cooled receiver) 13.1 g (47%), bp 108-110°C (5 mm) (Note 8). 

A soln of Z-AIle-OH (20 mmol) in AcQ (3 mL) and SOQ2 (9 mL) was stirred at rt for 2 h. After removal of the solvent under reduced pressure, dry CC14 (30 mL) was added to the crystalline residue and the resulting soln was concentrated. This procedure was repeated three times. The residual crystals were recrystallized (cyclohexane) to give AIle-NCA as colorless needles yield 90% (E/Z) mixture 3 2 mp 100-101 °C. The mixture was recrystallized repeatedly to give only the E-isomer mp 122-123 °C. 

This unit provides three protocols for which there are established procedures for various matrices. The Basic Protocol describes water removal and quantitation after a sample is placed in a convection oven. It is probably the method of choice when one does not know which method to choose when dealing with an unknown matrix, or when one looks at samples that foam excessively in the vacuum oven method or react, such as popcorn under vacuum. Alternate Protocol 1 describes water removal and quantitation after a sample is placed in a vacuum oven. Because it is at reduced pressure, drying times are slightly reduced compared to the convection method. In addition, drying temperatures < 100°C are possible, which is important for samples that may decompose at higher drying temperatures. Alternate Protocol 2 describes water removal using a microwave source where such analyzers measure and calculate loss automatically. 

The oily upper layer of chloronitrobenzene is washed with water, then with a sodium cMbonate solution, Mid again with water, followed by drying under reduced pressure. Drying of the product is necessary to prevent corrosion of the crystallizers. In this way, 4850 kg of crude chloronitrobenzene (m, p. 52°C) are obtained, a yield equivalent to 98% of the theoretical. 

A mixture consisting of methoxypolyethylene glycol (30,000 daltons 60% solution in toluene 3.30 g), 30ml of toluene, and butylated hydroxytoluene (0.004 g) were azeotropically dried by distilling off toluene under reduced pressure. Dried methoxypolyethylene glycol was then dissolved in 15 ml toluene and treated with 4 ml of l.OM potassium t-butoxide in t-butanol, 4-chloro-butyraldehyde diethyl acetal (0.00277 mol), and potassium bromide (0.05 g). The mixture was stirred overnight... 

Preparation The reagent can be prepared by neutralization of a 10% aqueous solution of teira-n-hutylammonium hydroxide with 48% hydrofluoric acid, concentration under reduced pressure, drying by azeotropic distillation under reduced pressure using 1 1 benzene-acetonitrile, and final drying at 30° and 0,5 mm. for 20 hr. For another preparation see Fowler et al. ... 

Final removal of solvent Drying at reduced pressure Drying at atmospheric pressure Drying with infra-red radiation Soaking the powder... 

Sample preparation Extract needles with MeOH, concentrate the extract under reduced pressure at <30°, partition concentrate with 0.8 volumes of water and 0.8 volumes of chloroform, repeat the extraction with 0.6 volumes chloroform then 0.4 volumes chloroform, concentrate under reduced pressure, dry under vacuum at 35-40°, dissolve in MeCN/water, inject an aliquot. 

Tatemoto, Y. and Miyazawa, K., Drying of suspensions in a fluidized bed of inert particles under reduced pressure. Drying Technol, 29,1204-1209, 2011. 

Kozanoglu, B., Flores, A., Guerrero-Beltran, J.A., and Welti-Chanes, J., Drying of Pepper seed particles in a superheated steam fluidized bed operating at reduced pressure, Drying TechnoL, 30, 884-890, 2012. 

Tatemoto, Y, Mawatari, Y, Sugita, K., Noda, K., and Komatsu, N., Drying characteristics of porous materials in a fluidized bed under reduced pressure, Drying TechnoL, 23, 1257-1272, 2005. 

M. Eslamian, N. Ashgriz Evaporation and evolution of suspended solution droplets at atmospheric and reduced pressures. Dry Technol. 25 (4-6), 999-1010 (2007). 

Titanium tetraisopropoxide Ti(0-iPr)4 (TIP) was hydrolysed in an ethanol solution of glacial acetic acid at room temperature. TIP was added drop-wise in ethanol and acetic acid solvent under vigorous stirring until a clear solution was formed. Water (0.05% v/v) was added under stirring and the solution became white. This solution was stirred for 6 h. TIP, ethanol and acetic acid were maintained in the ratio of 1 100 0.05, respectively. The solution was filtered and washed with deionized water twice. The filtrate was dried at 60 °C for 12 h under reduced pressure. Dry powder was calcined at 600 and 900 °C for 2 h and will be referred to as A (anatase) and R (rutile). 

The plate is developed with 1 1 ether (anhydrous)-petroleum ether (b.p. 35°-60°). Rj APA-Br, 0.63. APAA-Br has a lower Rf value than APA-Br, and the two are readily separated. APAA-Br is eluted from the silica gel with ether, and the ether solution is concentrated to a few milliliters under reduced pressure, dried (MgS04), and filtered. The residual ether is evaporated under a nitrogen stream to give 6.9 mg (0.023 mmole, 53%) of [carhoni/(- C]APAA-Br. The product is stored as a solution in anhydrous ether at —20°. 

After completion of the reaction, allow the system to reach room temperature, remove the upper phase by means of a pipet, and evaporate the solvent under reduced pressure. Dry the remaining residue under vacuum to give the pure coupling products. 

A S. commune fungus is cultured for 4 to 8 days at 28° C and then the fungus is removed as precipitate after being diluted and centrifuged. It is filtered and reduced pressure-dried after it is dehydrated using 35% methanol and ether. 

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