Tartaric acid, additive

Ions released into the matrix as the cement sets may interact with the organic part of the matrix. Metal ions, such as Ca + and AP+, may be chelated by car-boxylate groups, either on the polymer or on the tartaric acid additive. These have been considered in reasonable detail in the literature [230]. What has received far less attention is the possibility that fluoride ions might interact with carboxylic acid groups, either to modify the setting reaction or to become relatively securely anchored within the set cement. This possibility was raised in a review published in 1998 [230], but has not been followed up subsequently. It is based on the well-established observation that fluoride ion will form extremely strong hydrogen bonds with carboxylic acids in aqueous solution. They are of the type ... 

A number of the plications also list L-tartaric acid and D-glucaric acid as having comparable properties, both being hydroxy acids and chelators. When inexpensive glucaric acid becomes commercially available on a significant scale, it has applications waiting for a supply and could overtake uses now dominated by tartaric acid. Additional applications unique to glucaric acid will also benefit fiom a dependable source. 

Silica, If present, separates with the lead sulfate as does tungsten, niobium, tantalum, barlvun and less completely strontliim and calcium. Bismuth, antimony and silver contaminate the lead to some extent. The copreclpltatlon of antimony Is decreased by addition of tartaric acid. Addition of alcohol to the sulfate solution decreases the solubility of lead sulfate but Increases contamination by silver, bismuth or calcium. The normal separation based on the sulfate Involves dissolution of the lead sulfate In ammonium acetate solution. Hydroxide... 

A useful catalyst for asymmetric aldol additions is prepared in situ from mono-0> 2,6-diisopropoxybenzoyl)tartaric acid and BH3 -THF complex in propionitrile solution at 0 C. Aldol reactions of ketone enol silyl ethers with aldehydes were promoted by 20 mol % of this catalyst solution. The relative stereochemistry of the major adducts was assigned as Fischer- /ir o, and predominant /i -face attack of enol ethers at the aldehyde carbonyl carbon atom was found with the (/ ,/ ) nantiomer of the tartaric acid catalyst (K. Furuta, 1991). 

The FCC is to food-additive chemicals what the USP—NF is to dmgs. In fact, many chemicals that are used in dmgs also are food additives (qv) and thus may have monographs in both the USP—NF and in the FCC. Examples of food-additive chemicals are ascorbic acid [50-81-7] (see Vitamins), butylated hydroxytoluene [128-37-0] (BHT) (see Antioxidants), calcium chloride [10043-52-4] (see Calcium compounds), ethyl vanillin [121-32-4] (see Vanillin), ferrous fumarate [7705-12-6] and ferrous sulfate [7720-78-7] (see Iron compounds), niacin [59-67-6] sodium chloride [7647-14-5] sodium hydroxide [1310-73-2] (see lkaliand cm ORiNE products), sodium phosphate dibasic [7558-79-4] (see Phosphoric acids and phosphates), spearmint oil [8008-79-5] (see Oils, essential), tartaric acid [133-37-9] (see Hydroxy dicarboxylic acids), tragacanth [9000-65-1] (see Gums), and vitamin A [11103-57-4]. 

Similar polyacetals were prepared by BASF scientists from CO-aldehydic aUphatic carboxyUc acids (189,190) and by the addition of poly(hydroxycarboxyhc acid)s such as tartaric acid to divinyl ethers (191) as biodegradable detergent polymers. 

Sodium (and potassium) tetrathionate, M2S4O5, can be made by oxidation of thiosulfate by I2 (p. 714) and the free acid liberated (in aqueous solution) by addition of the stoichiometric amount of tartaric acid. 

Pota.ssium pentathionate, K2SSO6, can be made by adding potassium acetate to Wackenroder s solution and solutions of the free acid HiSsOf, can then be obtained by subsequent addition of tartaric acid. 

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). 

Two mols, for example, 270 grams, of racemic a-methylphenethylamine base are reacted with one mol (150 grams) of d-tartaric acid, thereby forming dl-a-methylphenethylamine d-tartrate, a neutral salt. The neutral salt thus obtained is fully dissolved by the addition of sufficient, say about 1 liter, of absolute ethanol, and heating to about the boiling point. The solution is then allowed to cool to room temperature with occasional stirring to effect crystallization. The crystals are filtered off and will be found to contain a preponderance of the levo enantiomorph. 

The residual solid in the mother liquors is repeatedly and systematically crystallized, yielding a further fraction of 1-a-methylphenethylamine d-tartrate which may be purified by recrystallization. d-a-Methylphenethylamine may be readily recovered from the mother liquors by the addition of tartaric acid thereto for the formation of acid tartrates and separation of d-a-methylphenethylamine d-bitartrate by crystallization. 

The undistilled aqueous tartaric acid solution was extracted with three 1-liter portions of ethyiene dichloride, and was then brought to a pH of about 8.5 to 9.5 by the addition of 28% aqueous ammonium hydroxide. The ammoniacal solution was extracted with three 1-liter portions of ethylene dichloride the ethylene dichloride extracts were combined, were dried, and were evaporated in vacuo, yielding a residue of 3.35 grams of a iight-brown powder. 

The introduction of reversible redox indicators for the determination of arsenic(III) and antimony(III) has considerably simplified the procedure those at present available include 1-naphthoflavone, and p-ethoxychrysoidine. The addition of a little tartaric acid or potassium sodium tartrate is recommended when antimony(III) is titrated with bromate in the presence of the reversible... 

Determination of copper as copper(I) thiocyanate Discussion. This is an excellent method, since most thiocyanates of other metals are soluble. Separation may thus be effected from bismuth, cadmium, arsenic, antimony, tin, iron, nickel, cobalt, manganese, and zinc. The addition of 2-3 g of tartaric acid is desirable for the prevention of hydrolysis when bismuth, antimony, or tin is present. Excessive amounts of ammonium salts or of the thiocyanate precipitant should be absent, as should also oxidising agents the solution should only be slightly acidic, since the solubility of the precipitate increases with decreasing pH. Lead, mercury, the precious metals, selenium, and tellurium interfere and contaminate the precipitate. 

Addition reactions to aldehydes in the presence of the tartaric acid derived chiral auxiliaries (.S ..S )-l,2,3,4-tetramethoxybutane (5), (S,.S)-2,3-dimethoxy-A%V,/V, A,, -tctramethyl-l,4-bu-tanediamine (6) and (5,5)-2,3-bis[2-(dimethylamino)ethoxy]-Af,yV,A. iV -tetramethyl-l,4-bu-tanediamine (7) have been studied in detail9" u. Again there was low enantioselection (generally 10-55% ee). 

Addition of the analogous methyltitanium reagent to bcnzaldchydc afforded the addition product with only 59% ee34. Use of the methyltitanium reagent obtained via chiral modification by the tartaric acid derived diol 43, did not lead to an improvement of the enantioselectivity42. 

The (acyloxy)borane complex 9, readily available from tartaric acid derivative 8, also catalyzes aldol additions of silyl enol ethers34 and silylketene acetals3 5 in an enantioselective manner. Thus,. u -ketones 10 and /Thydroxy esters 12 are available34, as well as a-unsubstituted ketones 1135. 

Deacetylanisomycin (4) is synthesized using L-tartaric acid (1) as a precursor in 12% overall yield16. The key step is the diastereoselective addition of (4-methoxybenzyl)magnesium chloride to the C — N double bond of nitrone 2 at 0°C in the presence of 1 equivalent of ethylmagncsium-bromide diethyl ether complex in dichloromethane. This procedure affords a chromatograph-ically separable mixture of the hydroxylamines 3 a and 3 b in a diastereomeric ratio [(2R,35,4R)/ (25,35,47 )] 70 30 and 60% yield from 2. 

The glass polyalkenoate cement system was not viable until Wilson and Crisp discovered the action of (+)-tartaric acid as a reaction-controlling additive (Wilson Crisp, 1975,1976,1980 Wilson, Crisp Ferner, 1976 Crisp Wilson, 1976 Crisp, Lewis Wilson, 1979). It may be regarded as an essential constituent and is invariably included in glass polyalkenoate cements as a reaction-controlling additive. 

Crisp, Merson Wilson (1980) found that the addition of metal fluorides to formulations had the effect of accelerating cement formation and increasing the strength of set cements the effect was enhanced by the presence of (-I-)-tartaric acid (Table 5.13). Strength of cements formed from an SiOj-AljOg-Cag (P04)2 glass, G-247, can be almost doubled by this technique. 

L-Tartaric acid-derived disulfonamide ligand for additions of ZnEt2 to aldehydes. 

Scheme 4.8 Additions of ZnEtj to ketones with bis(hydroxycamphorsulfonamide) ligand based on tartaric acid.

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