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Tartaric water, addition

It is sufficient to determine in the two wines those components which are of special interest in relation to the scope of the analysis. If any differences occur, the way in which the wine has been treated will be evident. Thus, if a wine exhibits general and proportional deficiencies of its constituents, mere watering is proved, and the extent of this may be calculated. If, however, as frequently happens, besides watering, addition of tartaric add has occurred, the alcoholic strength will be lowered, but the acidity will not be lowered in the same proportion, and so on. [Pg.220]

The chiral catalyst was made from Raney nickel, which was prepared by addition in small portions of 3.9 g Raney nickel alloy to 40 ml water containing9 g NaOH. The mixture was kept at 100 C for 1 h, and then washed 15 times with 40 ml water. Chirality was introduced by treatment of the Raney nickel for I h at lOO C with 178 ml water adjusted to pH 3.2 with NaOH and containing 2g (S,S)-tartaric acid and 20 g NaBr. The solution was then decanted, and the modifying procedure was twice repeated. Hydrogenation over this catalyst of acetylacctone (100 atm, 100" C) in THF containing a small amount of acetic acid gave an isolated yield of chiral pentanediol of 44% (99.6% optical purity). [Pg.14]

If the metallisable dye is insoluble in water, a miscible solvent such as ethanol or ethylene glycol may be added. Polar solvents such as formamide or molten urea have sometimes been preferred. It is likely that such solvents will preferentially displace water molecules and coordinate with the chromium (III) ion as the first step in the reaction. If colourless organic chelates of chromium, such as those derived from oxalic or tartaric acid, are used instead of or in addition to hydrated chromium (III) salts, the difficulty of replacing the strongly coordinated water molecules in the first stage of the reaction is eliminated. In this way the initial reaction can be carried out at high pH without contamination by the precipitation of chromium hydroxide. Use of the complex ammonium chromisalicylate (5.12) in this connection should also be noted (section 5.4-1). [Pg.250]

Natural compounds are also applied as chiral ligands in enantioselective homogeneous metallo-catalysts. A classical example is the Sharpless epoxidation of primary allylic alcohols with tert-butyl hydroperoxide [37]. Here the diethyl ester of natural (R,R)-(+)-tartaric acid (a by-product of wine manufacture) is used as bi-dentate ligand of the Ti(iv) center. The enantiomeric excess is >90%. The addition of zeolite KA or NaA is essential [38], bringing about adsorption of traces of water and - by cation exchange - some ionization of the hydroperoxide. [Pg.114]

To a suspension of 1 g of lithium aluminum hydride in 10 ml of anhydrous tetrahydrofuran cooled in an ice bath was added dropwise a solution of 1.94 g of methyl 3-methyl-trans-4a-cisoid-4a,5a-cis-5a-l,4a,5,5a,10b,10c-hexahydro-7-dioxino[5,4-a]cyclopenta[b]benzofurancarboxylate in 40 ml of anhydrous tetrahydrofuran. After being stirred for 30 min at room temperature, the reaction mixture was cooled in an ice bath. The excess of lithium aluminum hydride was decomposed by the addition of ethyl acetate, and aqueous saturated solution of potassium sodium tartarate was added to the reaction mixture. After filtration of the mixture, the filtrate was concentrated and the residue was dissolved in 10 ml of methanol. After addition of 2 g of potassium carbonate to the solution, the mixture was stirred for 3 hours at room temperature and was concentrated. After water was added to the residue, the aqueous mixture was extracted 3 times with ethyl acetate. The combined organic layers were washed with water and saturated aqueous solution of sodium chloride, dried, and concentrated to give 2 g of crude crystals. The crude crystals were recrystallized from ethyl acetate-hexane to yield 1.49 g of the pure crystals of the titled compound (m.p. 124-125°C, yield 85%). [Pg.594]

A mixture of 61 grams l-phenyl-l-oxo-2-(N-methyl-N-ethanolamino)-propane hydrochloride and 100 cc 98-100% formic acid was refluxed at the boiling point at atmospheric pressure for 45 minutes on an oil bath. Thereafter, the oil bath temperature was increased to 180°C and as much of the excess unreacted formic acid as possible was distilled off. A vigorous evolution of carbon dioxide developed during the distillation, which ceased after approximately 45 additional minutes. The honey-yellow syrup which remained as the distillation residue was worked up by admixing it with about six volumes of water and adjusting the aqueous mixture to alkaline reaction with concentrated sodium hydroxide. An oily phase separated out which was extracted with ether. The ether extract was washed with water and dried over potassium carbonate. The solvent was distilled off and the distillation residue was fractionally distilled in vacuo. The base boils at 132°-133°C at 12 mm. The yield was 93% of theory. Reaction with tartaric acid gave the final product. [Pg.2698]

A mixture of 96.5 g 2-methylsulfonylphenothiazine, 50 g 2-(2-chloroethyl)-l-methylpiperidine, 62 g diethyl carbonate and 2 g sodium methylate was heated at 135°C for 1 hour and then at 180-190°C for 2.5 hours. The product was dissolved in benzene (500 ml) and the solution was extracted with 700 ml of 15% aqueous solution tartaric acid. The extract was washed with benzene. After addition of sodium carbonate solution to the extract was obtained a precipitate which was dissolved in benzene. This solution was washed with water and concentrated. 2-Methylsulfonyl-10-(2-(l-methyl-2-piperidyl)ethyl)phenothiazin was recrystallized from acetone, melting point 121-123°C. [Pg.3117]


See other pages where Tartaric water, addition is mentioned: [Pg.329]    [Pg.1200]    [Pg.463]    [Pg.166]    [Pg.201]    [Pg.22]    [Pg.40]    [Pg.103]    [Pg.144]    [Pg.2]    [Pg.304]    [Pg.527]    [Pg.175]    [Pg.456]    [Pg.242]    [Pg.598]    [Pg.9]    [Pg.268]    [Pg.368]    [Pg.499]    [Pg.725]    [Pg.874]    [Pg.891]    [Pg.936]    [Pg.1119]    [Pg.1145]    [Pg.1146]    [Pg.164]    [Pg.2]    [Pg.199]    [Pg.225]    [Pg.815]    [Pg.812]    [Pg.189]    [Pg.88]    [Pg.617]    [Pg.113]    [Pg.2018]    [Pg.3199]    [Pg.3286]    [Pg.3493]    [Pg.112]    [Pg.274]   
See also in sourсe #XX -- [ Pg.412 ]




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