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Crystallization stirring suspensions during

A solution of sodium methoxide, prepared from sodium (23 g) and dry methanol (500 mL), was added drop-wise at 0 °C to a stirred suspension of aminoacetonitrile hydrochloride (18, 100 g, 1.08 mol) in dry methanol (100 rnL). After stirring for 2 h at rt the precipitated sodium chloride was filtered off and the filtrate concentrated in vacuo. EtOAc (20 mL) was added and evaporated under reduced pressure to remove all traces of methanol. The oily residue was dissolved in dry EtOAc (100 mL) and anhydrous sodium sulfate added. After cooling, the precipitate was filtered off. The solution of crude aminoacetonitrile was used without further purification. This solution was added drop-wise during a period of 1 h to a vigorously stirred, ice-cooled solution of carbon disulphide (100 mL, 1.66 mol) in dry EtOAc (100 mL) under an N2 atmosphere. Continued mechanical stirring and water-free conditions were essential. The mixture was stirred at 0 °C for 1 h. The resultant precipitate was filtered off, washed with EtaO and dried, giving the product 50 as yellow crystals (99 g, 75 % on amount of sodium), m.p. 131 °C dec. IR (KBr) v max 1630, 1500 cm. ... [Pg.282]

Butyl lithium (10 ml, 1.64 mol in hexane) was added under nitrogen to a stirred suspension of triphenyl-2-pyrrolidinoethylphosphonium bromide (7.2 g) in dry toluene (75 ml). After 0.5 h, ((E)-3-(6-(4-toluoyl)-2-pyridyl)acrylate, vide supra, (4.8 g) in toluene (50 ml) was added. The suspension, initially orange, became deep purple, then slowly faded to yellow during 2 h heating at 75°C. The cooled solution was diluted with ether (150 ml) and treated with hydrochloric acid (50 ml, 2 mol). The aqueous phase was separated, washed with ether, and basified with potassium carbonate (ice) and extracted with ether. The mixture of isomeric esters obtained by evaporation was dissolved in ethanol (100 ml) containing sodium hydroxide solution (20 ml, 1 mol) and partially evaporated on the steam bath under reduced pressure for 5 min. The residual aqueous solution was neutralized with sulfuric acid (20 ml, 0.5 mol) and evaporated to dryness. The solid residue was extracted with hot isopropanol (3x50 ml) and the extracts were concentrated until crystallization commenced. The (E)-3-(6-(3-pyrrolidino-l-(4-tolyl)prop-l-(E)-enyl)-2-pyridyl)acrylic acid, melting point 222°C (dec. recrystallization from isopropanol) was obtained. [Pg.87]

Chloro-2-(3-methyl-4H-l,2,4-triazol-4-yl)benzophenone (Oxidation of 7-chloro-l-methyl-5-phenyl-s-trizolo[4,3-a]quinoline) A stirred suspension of 7-chloro-l-methyl-5-phenyl-s-triazolo[4,3-a] quinoline (2,94 g, 0.01 mol) in acetone (110 ml) was cooled in an ice-bath and treated slowly with a solution prepared by adding sodium periodate (2 g) to a stirred suspension of ruthenium dioxide (200 mg) in water (35 ml). The mixture became dark. Additional sodium periodate (8 g) was added during the next 15 minutes. The ice-bath was removed and the mixture was stirred for 45 minutes. Additional sodium periodate (4 g) was added and the mixture was stirred at ambient temperature for 18 hours and filtered. The solid was washed with acetone and the combined filtrate was concentrated in vacuum. The residue was suspended in water and extracted with methylene chloride. The extract was dried over anhydrous potassium carbonate and concentrated. The residue was chromatographed on silica gel (100 g) with 10% methanol and 90% ethyl acetate 50 ml fractions were collected. The product was eluted in fractions 10-20 and was crystallized from ethyl acetate to give 0.405 g of melting... [Pg.190]

Typical procedure. 1,3,5-Tricyanobenzene 1458 [1105] To a stirred suspension of 1,3,5-tricarbamoylbenzene 1457 (4.6 g, 22.2 mmol) in DMF (35 mL), thionyl chloride (6 mL) was added over a period of 1 h, maintaining the temperature at 60 °C. Stirring at this temperature was maintained for 6 h, during which time complete dissolution occurred. The resulting solution was poured into dilute aq. HCl (100 mL) to decompose unreacted SOCI2, giving a dense white precipitate. This solid was collected by filtration, washed with water until the washings were neutral to litmus, and dried at 120 °C for 14 h. Crystallization from ethanol and acetone yielded the product 1458 as colorless needles (1.50 g, 45%). [Pg.379]

Conduritol B Epoxide (FZ/). - Compound (VI), 5 g, (finely powdered) is suspended in 10 ml of water. Acetic acid (99%), 500 ml, and 20 g of p-nitroperbenzoic acid - are added and the suspension is stirred at 8°-10° overnight and then for 5 hr at room temperature. The mixture is concentrated under reduced pressure to a semisolid mass, which is stirred with 100 ml of water. p-Nitrobenzoic acid and unreacted peracid are filtered, and the filtrate is taken to a syrup. Methanol, 100 ml, is added, the preparation is again concentrated, and the residue is taken up in 100 ml of ethanol. The epoxide usually begins to crystallize during the first concentration. Crystallization is completed during 2 days at -20°. Yield, 4.2 g m.p., 157°-159°. [Pg.373]

A solution of 10.0 g. (0.25 mole) of sodium hydroxide in 250 ml. of water is prepared in a 1-1. round-bottomed flask equipped with a reflux condenser and a mechanical stirrer. Twenty-five grams (0.065 mole) of N,N-dimethylaminomethylferrocene methiodide is added to the solution. The resulting suspension is heated to reflux temperature with stirring. At this point the solid is in solution. Within 5 minutes oil starts to separate from the solution and trimethylamine starts to come off. At the end of 3.5 hours, at which time the evolution of the amine has virtually ceased, the reaction mixture is allowed to cool to room temperature. The oil generally crystallizes during the cooling. The mixture is stirred with 150 ml. of ether until the oil or solid is all dissolved in the ether. The ether layer is separated in a separatory funnel and the aqueous layer is extracted with two additional 150-ml. portions of ether. The combined ether extracts are washed once with water and dried over sodium sulfate. [Pg.52]

The following description is taken from U.S. Patent 3,116,203. A stirred solution of 75 g of 2-amino.2 -nitrobenzophenone in 700 ml of hot concentrated hydrochloric acid was cooled to 0°C and a solution of 21.5 g of sodium nitrite in 50 ml of water was added in the course of 3 hours. The temperature of the suspension was kept at 2° to 7°C during the addition. The resulting clear solution was poured into a stirred solution of 37 g of cuprous chloride in 350 ml of hydrochloric acid 1 1. The solid which had formed after a few minutes was filtered off, washed with water and recrystallized from ethanol. Crystals of 2-chloro-2 -nitrobenzophenone melting at 76° to 79°C were obtained. [Pg.371]


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