Citric acid ethyl ester

Citric acid, ethyl ester Citroflex 2 Citrofol AI E1505 Hydagen CAT TEC. 

A liquid detergent for dishes, vegetables, and fruit comprises the sodium salt of a-sulfo coconut acid ethyl ester (20%), an alkylamine oxide (5%), citric acid (0.5%), ethanol (50%), and water [78]. 

Beilstein Handbook Reference) AI3-00659 BRN 1801199 Citric acid, triethyl ester Citroflex 2 EINECS 201-070-7 Ethyl citrate Eudraflex FEMA No. 3083 HSDB 729 Hydragen CAT 2-Hydroxy-1,2,3-pnopanetricarboxylic acid, triethyl ester NSC 8907 ... 

Methyl, ethyl, n-propyl, isopropyl, n-hutyl, benzyl, cyclohexyl esters of formic, acetic, oxalic, succinic, tartaric, citric, benzoic, salicylic (and other substituted benzoic acids), phthalic and cinnamic acids phenyl esters of acetic, benzoic and salicylic acids. 

Tetrabromophenolphthalein Ethyl Ester-Silver Nitrate-Citric Acid Reagent... 

Tetra-bromophenolphthalein ethyl ester K salt Silver nitrate Citric acid... 

The protected O-glycosyl amino acid ester or O-glycosyl peptide ester (1 mmol) is stirred in morpholine (10 mL) or morpholine-dichloromethane (1 1) for 30 min. After addition of dichloromethane (100 mL), the solution is washed with diluted aqueous acid (citric acid or HC1 pH 4, 50 mL) and with water (4 x 50 mL), dried with NajSO, and concentrated in vacuo. The crude product is dissolved in 2-5 mL of ethyl acetate. During chromatography on silica gel (50 g) with petrolum ether ethyl-acetate (2 1), W-(9-fluorenylmethyl)morpho-line is eluted. Subsequently, the deblocked amino acid or peptide ester is eluted with methanol. 0-(2,3,4-Tri-0-benzoyl-(3-D- xylopyranosyl)-L-serine benzyl ester 14 yield, 0.63 g (98%) mp 55°C [a]D —41.4 (c 0.5, CH3OH). IV-(L-Asparaginyl-L-leucyl-)-0-(2,3,4,-0-benzoyl-(3-D-xylopyranosyl)-L-serine benzyl ester 17 yield, 0.85 g (98%) amorphous [a]D —42.3° (c 0.5 CH3OH). 

If hydrolysis of the methyl ester of the Laas is required, this can be achieved by dissolving the compound in DME and water and adding LiOH (-5 equivalents) and allowing the reaction to stir at room temperature overnight. The reaction mixture is then acidified to pH 4.0 with 5% citric acid solution and extracted into ethyl acetate (3 x 20 mL). The organic extracts are washed with saturated NaCl, dried with MgS04, filtered, and solvent removed. The purification of the resulting free acid depends on the compound to which the Laa has been coupled. 

Itaconic acid was isolated in 1836 from the pyrolysis products of citric acid (7) and the pol3mierization of the ethyl ester was observed by SwAETS in 1873 (2). While many patents relating to the acid and its esters as monomers have issued since that time, only recently have reports begun to appear in the scientific journals. The voluminous patent literature describes the use of polymeric itaconic acid derivatives in such applications as protective and decorative coatings, synthetic fibers, oil additives and rigid plastics as well as many others. Several summaries of the patent art and present commercial applications are available (3). Such information has been omitted from this review, which is directed primarily toward chemical behavior of the itaconic monomers and polymers. 

Nitrilotriacetlc acid was supplied by the Hampshire Chemical Co., Division of W. R. Grace Co., Nashua, New Hampshire. For feeding studies It was neutralized with 1 M sodium hydroxide to provide a 1% NTA solution. Ethyl nltrllotrlacetate was obtained as a clear colorless viscous oil by refluxing 30g of nltrllotrl-acetlc acid In 1 liter of absolute alcohol In the presence of 3g of toluenesulphonlc acid for forty-eight hours. The alcohol was removed by distillation from a water bath in vacuo, the residue mixed with 100 ml of 0.5 percent sodium bicarbonate solution and extracted with one liter of benzene. The benzene solution was extracted twice more with bicarbonate solution, washed with water and concentrated from a water bath In vacuo. The clear colorless residual oil was dissolved by shaking with an aqueous solution of 1.5 M citric acid and the volume adjusted by addition of distilled water to provide a final solution of 1% NTA ethyl ester as citric acid salt. 

To a solution of 10.7 g L-methionine ethyl ester hydrochloride (0.05 mol) in 200 mL THF was added 7.0 mL triethylamine (0.05 mol). The resulting salt was filtered. To the solution, 17.0 g (0.055 mol) Nps-leucine NCA was added and stirred at room temperature for 2 h. Then the solvent was evaporated under reduced pressure at 35°C, the residual oil was dissolved in 200 mL ethyl acetate, and the solution was washed with 5% of citric acid, 5% of sodium bicarbonate, and water and dried over Na2S04. The solution was concentrated in vacuum at 40°C to give an oil, which was crystallized by adding n-hexane. Further purification can be done from recrystallization in ethyl acetate. 

Synonyms Ethyl citrate 2-Hydroxy-1,2,3-propanetricarboxylic acid, triethyl ester TEC Triethyl-2-hydroxypropan-1,2,3-tricarboxylate Definition Triester of ethyl alcohol and citric acid Empirical C12FI20O7 Formula CsHsOjCOOCzFIsjs... 

Citrates n. Esters derived from citric acid. The tri-ethyl, -butyl, and -amyl citrates form a series of plasticizers. 

Triethyl citrate (ethyl citrate) n. (C2H5OO CCH2)2C(0H)C00C2H5. An ester of citric acid, used as a plasticizer for many thermoplastics including vinyls, cellulosics, and polystyrene. It has won FDA approval for use in food packaging. 

The rate of esterification of acetic, propionic, citric, butyric, malic, succinic, lactic, and tartaric acids at three different pH s over a 30- to 60-day period was determined by Espil and Peynaud (1936). They showed that none of the ethyl esters of the polyhydric alcohols contribute to the aroma and would not even if present at ten times their normal amounts. Tomaghelli (1937) studied the rate of esterification of the system acetic acid-ethyl alcohol and that of saponification of the system ethyl acetate-water at 100° C. (212° F.) for 500 hours and at 150° C. (302° F.) for 320 hours. 

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