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Tetrahydrofuran with water

Treatment ofRu3(CO)11(Ph2PC=CPr ) in tetrahydrofuran with water or ethanol affords up to 30% of the red tetranuclear clusters (90 R = H or Et, respectively) (135). In these, the cleavage of the P-C bond is accompanied by addition of OH or OEt to the cluster, with transfer of hydrogen to the / -carbon. Unusually, the hinge metal atoms are separated by 3.455 A, too far for a normal metal-metal interaction this has the result of bringing the HyO and/i4-C atoms to within 2.65 A of each other, suggesting the possibility of facile H transfer between the two atoms. [Pg.121]

Within the last several years HPLC separations have been optimized in terms of the most appropriate mobile phase composition for a particular set of solutes by exploring the whole plane of solvent selectivities using this solvent classification scheme with a minimal number of measurements in statistically-designed experiments. For reversed phase HPLC systems, the selectivity triangle is often defined by methanol, acetonitrile, and tetrahydrofuran with water as the diluent (37). [Pg.149]

In LC analysis, the usual approach adopted is to employ the reversed-phase mode using a Cjg-type stationary phase. A typical eluent would be a binary phase based on methanol or tetrahydrofuran with water. The latter solvent mixture has the advantage that the strong solvent capability of the tetrahydrofuran readily dissolves the polymeric components... [Pg.41]

Terminal alkyne anions are popular reagents for the acyl anion synthons (RCHjCO"). If this nucleophile is added to aldehydes or ketones, the triple bond remains. This can be con verted to an alkynemercury(II) complex with mercuric salts and is hydrated with water or acids to form ketones (M.M.T. Khan, 1974). The more substituted carbon atom of the al-kynes is converted preferentially into a carbonyl group. Highly substituted a-hydroxyketones are available by this method (J.A. Katzenellenbogen, 1973). Acetylene itself can react with two molecules of an aldehyde or a ketone (V. jager, 1977). Hydration then leads to 1,4-dihydroxy-2-butanones. The 1,4-diols tend to condense to tetrahydrofuran derivatives in the presence of acids. [Pg.52]

Lithium aluminum hydnde reacts violently with water and alcohols so it must be used m solvents such as anhydrous diethyl ether or tetrahydrofuran Following reduc tion a separate hydrolysis step is required to liberate the alcohol product... [Pg.629]

While keeping the collected deuterioammonia at dry ice-isopropyl alcohol temperature, lithium wire (10 mg) is added, followed by a solution of 3/3-hydroxy-5a-cholest-7-en-6-one (161 50 mg) in anhydrous tetrahydrofuran (4 ml). The reaction mixture is stirred for 20 min, the cooling bath is then removed and the ammonia is allowed to boil under reflux for 40 min. A saturated solution of ammonium chloride in tetrahydrofuran is added dropwise until the deep blue color disappears and then the ammonia is allowed to evaporate. The residue is extracted with ether and the organic layer washed with dilute hydrochloric acid and sodium bicarbonate solution and then with water. Drying and evaporation of the solvent gives a semicrystalline residue which is dissolved in acetone and oxidized with 8 N chromic acid solution. After the usual workup the residue is dissolved in methanol containing sodium hydroxide (0.2 g) and heated under reflux for 1 hr to remove any deuterium introduced at C-5 or C-7. (For workup, see section II-B). [Pg.191]

A solution of the acylated thiocyanatohydrin in a minimal amount of 5% potassium hydroxide in diglyme (other solvents such as methanol, ethanol or tetrahydrofuran have also been used) is stirred for 2 days at room temperature. Water is added to the reaction mixture to precipitate the product which is filtered or extracted with ether (or chloroform). The ether extract is washed several times with water, dried (Na2S04), and concentrated under vacuum. The thiirane usually can be crystallized from an appropriate solvent pair. Chromatography over alumina has been used for the purification of episulfides. [Pg.45]

A slow stream of purified and dried acetylene is passed for 3 hr through a solution containing 25 ml (75 mmoles) of a 3 TV solution of methyl magnesium bromide and 100 ml of anhydrous tetrahydrofuran. A solution consisting of 5 g (17 mmoles) of 3)5-hydroxyandrost-5-en-17-one and 50 ml of anhydrous tetrahydrofuran is then added and the mixture is boiled at reflux for 15 min, during which time a heavy precipitate forms. The reaction mixture is cooled and poured into 1 liter of water containing 20 ml of concentrated sulfuric acid. The crude product is obtained as a precipitate, which is filtered, washed with water and dried to yield 5.2 g of 17a-ethynylandrost-5-ene-3, 17 -diol mp 228-232°. One crystallization from chloroform-hexane yields 4.5 g (83%) mp 238-240° [[Pg.73]

A solution of the monosodium salt of diacetylene in 300 ml of liquid ammonia is prepared from 13.8 g (0.6 g-atoms) sodium and 24.6 g (0.2 moles) l,4-dichlorobut-2-yne. To this mixture is added a suspension of 5 g (17.6 mmoles) 3-methoxyestra-l,3,5(10)-trien-17-one in anhydrous tetrahydrofuran at —40° and the reaction mixture is stirred and maintained at this temperature for 2 hr. Ammonium chloride is then added and the ammonia is allowed to evaporate overnight. The residual solids are extracted with methylene dichloride and the extracts washed with water, dried over magnesium sulfate, and evaporated at 70°. The resultant dark gum is... [Pg.74]

A solution of 10 g of this compound in 80 ml of tetrahydrofuran is added, with cooling, during 5 min, to a solution of 4.8 g of lithium aluminum hydride in 60 ml of tetrahydrofuran, and the mixture refluxed for 2.25 hr then cooled in an ice bath and treated with 60 ml of acetone, followed by 200 ml of ether and 72 ml of 2 A sodium hydroxide. The mixture is filtered, the cake washed with 50 ml of acetone, and the combined filtrate washed with water, dried over sodium sulfate and evaporated under reduced pressure. The residue is crystallized from acetone to give 6.05 g (68 %) of the enamine. [Pg.195]

Alkali-metal graphites are extremely reactive in air and may explode with water. In general, reactivity decreases with ease of ionization of M in the sequence Li > Na > K > Rb > Cs. Under controlled conditions H2O or ROH produce only H2, MOH and graphite, unlike the alkali-metal carbides M2C2 (p. 297) which produce hydrocarbons such as acetylene. In an important new reaction CgK has been found to react smoothly with transition metal salts in tetrahydrofuran at room temperature to give the corresponding transition metal lamellar compounds ... [Pg.295]

To the cooled solution is added dropwise with stirring, a solution of 64 g (0.48 mole) of -amyl nitrate in 100 ml of dry tetrahydrofuran during a period of 1 hour. The solution is finally allowed to warm to room temperature overnight. Work-up is carried out by adding an excess of ice-acetic acid, diluting with water, and extracting the aqueous solution several times with ether. The ether extracts are washed thoroughly... [Pg.65]

A 1.5 to 2 M solution of methylsulfinyl carbanion in dimethyl sulfoxide is prepared under nitrogen as above from sodium hydride and dry dimethyl sulfoxide. An equal volume of dry tetrahydrofuran is added and the solution is cooled in an ice bath during the addition, with stirring, of the ester (0.5 equivalent for each 1 equivalent of carbanion neat if liquid, or dissolved in dry tetrahydrofuran if solid) over a period of several minutes. The ice bath is removed and stirring is continued for 30 minutes. The reaction mixture is then poured into three times its volume of water, acidified with aqueous hydrochloric acid to a pH of 3-4 (pH paper), and thoroughly extracted with chloroform. The combined extracts are washed three times with water, dried over anhydrous sodium sulfate, and evaporated to yield the jS-ketosulfoxide as a white or pale yellow crystalline solid. The crude product is triturated with cold ether or isopropyl ether and filtered to give the product in a good state of purity. [Pg.94]

Preparation of 9a-Fluoro-110,17a,21-Trihydroxy-160-Methyl-4-Pregnene-3,2O-Dione 21-Acetate To a solution of 200 mg of 9(3,11(3-epoxy-1 7a,21-dihydroxy-16(3-methyl-4-pregnene 3,20-dione 21-acetate in 2 ml of chloroform and 2 ml of tetrahydrofuran in a polyethylene bottle at -60°C was added 2 ml of a 2 1 (by weight) mixture of anhydrous hydrogen fluoride and tetrahydrofuran. After 4 hours at -10°C the mixture was cooled to -60°C and cautiously added to a stirred mixture of 30 ml or 25% aqueous potassium carbonate and 25 ml of chloroform kept at -5°C. The aqueous phase was further extracted with chloroform and the latter phase washed with water and dried over magnesium sulfate. The residue on crystallization from acetone-ether gave pure 9a-fluoro-11(3,17a,21-trihydroxy-16(3-methyl-4-pregnene-3,20-dione 21-acetate. [Pg.166]

A solution of 1.0 g of 1,4 (11 )-pregnatriene-170 1 -diol-3 0-dione-21 -acetate and 5,0 g of lithium chloride in 40 ml of glacial acetic acid is treated with 0.410 g of Nchlorosuccinimide, followed by 0.104 g of anhydrous hydrogen chloride dissolved in 2.5 ml of tetrahydrofuran. The reaction mixture is stirred for 2 hours and poured into ice water. The crude product Is filtered and washed with water to give 1.12 g of solid material, which is recrystallized from acetone-hexane to give substantially pure 90 ,11 -dichloro-1,4-pregnadiene-170 ,21 -diol-3,20-dione-21 -acetate MP 246°C to 253°C (dec.). [Pg.473]

After this reaction-time, the evolution of hydrogen is ceased. Then there are added successively 60 parts dimethylformamide and 8 parts of p-chlorobenzylchloride and stirring and refluxing is continued for another two hours. The tetrahydrofuran is removed at atmospheric pressure. The dimethylformamide solution is poured onto water. The product, 1-[2,4-dichloro-/3-(p-chlorobenzyloxy)phenethyl] imidazole, is extracted with benzene. The extract is washed with water, dried, filtered and evaporated in vacuo. From the residual oily free base, the nitrate salt is prepared in the usual manner in 2-propanol by treatment with concentrated nitric acid, yielding, after recrystallization of the crude solid salt from a mixture of 2-propanol, methanol and diisopropylether, 1-[2,4-dichloro-/3-(p-chlorobenzyl-oxylphenethyl] imidazole nitrate MP 162°C. [Pg.552]

To a solution of 2.4 g of pregna-1,4,9(11)-triene-21-ol-3,20-dione-[17o ,16a-d] -2 -methylox-azoline 21 -acetate in 24 ml of tetrahydrofuran, 12.8 ml of 0.46N perchloric acid are added at 15°C under stirring. N-bromoacetamide (1.1 g) is then added to the mixture which is kept far from light, and stirred for 4 hours at room temperature. After lowering the temperature to 10°C, a saturated solution of sodium bisulfite is added in order to decolorize the mixture, which is then poured into 120 ml of Ice water. A product separates, which is collected by filtration, washed with water and then dried, thus obtaining 2.81 g of crude 9a-bromo-pregna-... [Pg.652]

A solution of 23.7 grams of 2-bromoacetamido-2 -fluorobenzophenone in tetrahydrofuran (100 cc) was added to liquid ammonia (approximately 500 cc) and allowed to evaporate overnight. The residue was treated with water (1 liter) and the crystals filtered off and refluxed in toluene (100 cc) for 30 minutes. The mixture was treated with decolorizing carbon (Norite) and filtered over Hyflo. The solution was concentrated to a small volume (25 cc) cooled, diluted with 20 cc of ether and allowed to stand. The product was re-crystallized from acetone/hexane to give 5-(2-fluorophenyl)3H-1,4-benzodiazepin-2(1 H)-one as white needles melting at 180° to 181°C. [Pg.666]

Synthesis of 16,16-dimethyl-trans-A -PGEi 2.35 g of the bis-tetrahydropyranyl ether were dissolved in 6 ml of tetrahydrofuran and 60 ml of 65%-acetic acid aqueous solution and the solution stirred at 60°C to 70°C for 20 minutes. The reaction mixture was extracted with ethyl acetate, and the organic layer was washed with water, dried and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel using ethyl acetate-cyclohexane (2 3) as eluent to yield 270 mg of the title compound. [Pg.719]

The residue was dissolved in 75 ml of tetrahydrofuran, treated with charcoal, and sodium sulfate and filtered. This solution was added to a solution in 250 ml of tetrahydrofuran of phenyl magnesium bromide prepared from 17.7 ml (0.17 mol) of bromobenzene. This mixture was stirred and heated under reflux for 1 hour. It was then cooled and diluted with 400 ml of ether and sufficient 3N hydrochloric acid to make it acidic. The aqueous phase was separated, adjusted to pH 8 with 3N sodium hydroxide and extracted 3 times with 200 ml of ether. The ether extracts were combined, washed with water and dried over sodium sulfate. The residue left on removal of the ether in vacuo was crystallized from petroleum ether to give 3.3 g of 7-chloro-2,3-dihvdro-1-methyl-5-phenvl-1 H-1,4-benzodiazepine, according to U.S. Patent 3,624,703. [Pg.910]

Preparation of 11 -Hydroxy-6a-Methylprogesterone A mixture of 2.68 g of 11-keto-6(3-methylprogesterone 3,20-bis-(ethylene ketal), 161 ml of tetrahydrofuran (previously distilled from lithium aluminum hydride), 1.34 g of lithium aluminum hydride and 14.5 ml of absolute ether was stirred and refluxed under nitrogen for 1.5 hours, then 27 ml of water was added cautiously, to decompose excess hydride. The resulting mixture was filtered and the filter cake was washed with 135 ml of ether. The combined filtrate and wash was shaken with 135 ml of water and separated. The aqueous layer was washed with four 55-ml portions of ether, then the organic layer and the washes were combined, washed once with water, and evaporated to dryness under diminished pressure leaving a tan residue. [Pg.918]

To a suspension of 73.9 g of 1 -methyl-5-nitro-3-phenylindole-2-carbonitrile in 1.5 liters of dry tetrahydrofuran Is added dropwise a solution of 126 g of boron trifluoride etherate in 220 ml of dry tetrahydrofuran with stirring for 2 hours. After addition, stirring is continued for an additional 3 hours. To the reaction mixture Is added dropwise 370 ml of water and then 370 ml of concentrated hydrochloric acid with stirring under ice-cooling. [Pg.1083]

Preparation of 2-Cyctopropylmethylamino-5-Chlorobenzhydrol To a slurry of 94.8 g (2.47 mols) of lithium aluminum hydride in 1.2 liters of tetrahydrofuran is added with stirring a solution of 356 g (1.18 mols) of 2-cyclopropylcarbonylamido-5-chlorobenzo-phenone in 1.8 liters of tetrahydrofuran. The addition takes 80 minutes while maintaining gentle refluxing, and the reaction mixture is then refluxed overnight and allowed to cool to room temperature over a period of 3 days. The complex formed in the reaction mixture is then hydrolyzed with water. [Pg.1278]

Alternative Step D Reduction with a Reductate — Sucrose (1 kg) is dissolved in water (9 liters) in a 20-liter bottle equipped with a gas trap. Baker s yeast Saccharomyces cerevisiae, 1 kg) is made into a paste with water (1 liter) and added to the sucrose solution with stirring. After lively evolution of gas begins (within 1 to 3 hours), 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole hydrogen maleate [1.35 mols, prepared by reaction of the 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole with an equimolar quantity of maleic acid in tetrahydrofuran]. The mixture is allowed to stand until fermentation subsides, after which the bottle is kept in a 32°C incubator until all fermentation has ended (in approximately 1 to 3 days). The yeast is filtered off with addition of diatomaceous earth and the filtrate is evaporated to dryness to give S-3-mor-pholino-4/3-tert-butylamino-2-hydroxypropoxy)-1,2,5-thiadiazole, MP 195° to 198°C (as hydrogen maleate), according to U.S. Patent 3,619,370. [Pg.1490]


See other pages where Tetrahydrofuran with water is mentioned: [Pg.576]    [Pg.151]    [Pg.156]    [Pg.98]    [Pg.71]    [Pg.576]    [Pg.151]    [Pg.156]    [Pg.98]    [Pg.71]    [Pg.284]    [Pg.582]    [Pg.97]    [Pg.32]    [Pg.561]    [Pg.63]    [Pg.243]    [Pg.435]    [Pg.459]    [Pg.486]    [Pg.139]    [Pg.166]    [Pg.206]    [Pg.254]    [Pg.984]    [Pg.1063]    [Pg.21]    [Pg.298]    [Pg.401]    [Pg.78]   
See also in sourсe #XX -- [ Pg.610 , Pg.611 ]




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