H-charcoals

Typically, dry potassium nitrate is pulverized in a ball mill. Sulfur is milled into cellular charcoal to form a uniform mix in a separate ball mill. The nitrate and the sulfur—charcoal mix are screened and then loosely mixed by hand or in a tumbling machine. Magnetic separators may be used to ensure the absence of ferrous metals. The preliminary mix is transferred to an edge-mimer wheel mill with large, heavy cast iron wheels. A clearance between the pan and the wheels is required for safety purposes. The size of this gap also contributes to the density of the black powder granules obtained. Water is added to minimize dusting and improve incorporation of the nitrate into the charcoal. The milling operation requires ca 3 to 6 h. 

Hydroxy-6-cyanoclnnollne (4). A cooled suspension of 3 (1.0 g, 6 1 mmol) in 2N Hi (15 mL) was treated with 15% NaNOa (15 mL) under stirnrvg The mixture was heated on a wa bath for 1 h, cooled, filtered and the crude 4 was dissolved m Na2C03 solution, treated with Nomte charcoal HOAc precipitated 4 Recrysialllzaiion from EtOH attorded 4, mp 284-285°(... 

Phospho-L-threonine (L-threonine-O-phosphate) [1114-81-4] M 199.1, m 194 (dec), [a]p -7.37 (c 2.8, H2O) (pK as above). Dissolve in the minimum volume of H2O, add charcoal, stir for a few min, filter and apply onto a Dowex 50W (H" " form) then elute with 2N HCI. Evaporate the eluates under reduced pressure whereby the desired fraction produced crystals of the phosphate which can be recrystd from H2O-MeOH mixtures and the crystals are then dried in vacuo over P2O5 at 80 . [de Verdier Acta Chem Scand 7 196 7955.]... 

Propenyl)aniline (1, 1.0 g, 7.52 mmol), PdCl2(CH3CN)2 (0.195 g, 0.75 mmol), benzoquinone (0.812 g, 7.52 mmol), and LiCl (3.158 g, 75.2 mmol) were combined in THF (95 mL). After 5 h at reflux, the solvent was removed and the residue was stirred with ether and decolorizing charcoal for approximately 20 min and filtered. The filtrate was washed five times with 50-mL portions of 1 M NaOH. The solvent was removed by vacuum, and the residue was placed on a silica gel column and eluted with 3 1 petroleum ether/ether. 2-Methylindole (2, 0.818 g, 86%) was collected as a white, crystalline solid, identical with authentic material. ... 

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. 

A mixture of an amide 1 (2.5 g) and PPA (20 g) was stirred and heated at 150-160 0 for 3 h. The cooled mixture was poured into H20 and the resulting precipitate was filtered off and dissolved in Et20. The ethereal solution was washed with aq K2C03. stirred with charcoal, dried and evaporated. The residue was recrystallized (benzene/ petroleum ether). 

Diethyl malonate or a derivative (0.25 mol) and benzene-1,2-diamine (27 g, 0.25 mol) were added to a solution of NaOEt prepared from sodium (11.5 g. 0.5 g-atom) and EtOH (300 mL). The EtOH was distilled off, finally under reduced pressure, and the residue was heated at 180-200 C under N2 for 4 h and then stirred with ice. The mixture was acidified with coned HC1 and the resulting solid was collected, washed with H20 and recrystallized (EtOH) with the addition of decolorizing charcoal if necessary. 

The ester 3 (R1 = H, R2 = (CH2)3NMe2 23 g. 67 mmol), obtained by catalytic hydrogenation of the corresponding nitro compound, was heated in refluxing xylene (700 mL) for 15 h. The solvent was removed under reduced pressure and the residue was dissolved in 1 M HOAc and charcoal was added. The filtered solution was made alkaline with coned NH3 and the resulting precipitate was extracted with CHC1V The extract was washed with H20, dried and evaporated in vacuo, leaving the product yield 9.25 g (47%) mp 151-152 C. 

A solution of 1 l,12-dihydrodibenzo[r,g][l,2]diazocine (1 1.5 g, 7.1 mmol) in CC14 (120mL) was stirred with NBS (1.5 g. 8.43 mmol) and refluxed for 12 h. The mixture was cooled and filtered, the filtrate was evaporated to dryness, and the resulting dark residue was extracted with boiling cyclohexane (100 mL). The extract was decolorized with charcoal and the filtrate was evaporated to dryness to afford crude 11-bromo-l l,12-dihydrodibenzo[c,g][l,2]diazocine (2) yield 1.1 g (54%) mp 105-106 C (after recrystallization from cyclohexane). 

Adsorption beds of activated carbon for the purification of citric acid, and adsorption of organic chemicals by charcoal or porous polymers, are good examples of ion-exchange adsorption systems. Synthetic resins such as styrene, divinylbenzene, acrylamide polymers activated carbon are porous media with total surface area of 450-1800 m2-g h There are a few well-known adsorption systems such as isothermal adsorption systems. The best known adsorption model is Langmuir isotherm adsorption. 

A current 1.00-g sample of carbon shows 921 disintegrations per hour. If 1.00 g of charcoal from an archaeological dig in a limestone cave in Slovenia shows 5.50 X 103 disintegrations in 24.0 h, what is the age of the charcoal sample ... 

A solution of sodium methoxide (80 mmol) in methanol (40 mL) is added to silica gel (2.7 g, 45 mmol) followed by a solution of catechol (13.2 g, 120 mmol) in methanol (40 mL). The resulting mixture is stirred and heated under reflux for 18 h. The methanol is then evaporated and the solid residue washed with ether. The black sohd is dissolved in THF (400 mL) and the resulting solution is heated for 1 h in the presence of charcoal. After filtration and evaporation of the solvent the sodium tris(benzene-l,2-diolato)silicate 80 is isolated as a white powder (12.53 g, 70% Scheme 2.20) [93]. 

Yamazaki, H. et ah. Effects of the dietary snpplements, activated charcoal and copper chlorophyUin, on urinary excretion of trimethylamine in Japanese trimethylaminnria patients. Life ScL, 74, 2739, 2004. 

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