Ethyl cyanacetate

It is now applied more widely to include malonic acid derivatives, such as diethyl monoethyl-malonate, ethyl cyanacetate, etc. Various amines may be used as catalysts, and usually the most effective is piperidine (hexahydro-pyridine) a mixture of piperidine and pyridine, or pyridine alone, is also often used. 

The acid was prepared in considerable quantities by the following rather complicated series of reactions. When ethyl yS-iodopropionate and the sodium derivative of ethyl cyanacetate are allowed to interact in... 

Ethyl-cyanacetic ester. Ill parts of the above ester is added and dissolved in a solution of 92 parts sodium in 1,500 parts of dry ethanol. 750 parts of ethyl iodide are gradually added to the mixture, while it boils gently under reflux. Filter the sodium iodide that forms from the solution and distill off the alcohol. After adding water to the residue the ester separates and is purified by vacuum distillation. Collect the fraction around 125° at 4 mm. 

Into a 500 ml spherical flask, equipped with a dropping funnel, a mechanical stirrer, a thermometer and a condenser, above which was disposed a calcium chloride trap, were introduced 16.95 g (0.141 mol) of ethyl cyanacetate and 40.69 g (0.33 mol) of n-propyl bromide. This mixture was heated to 45°C and then there was added thereto, slowly and while stirring, the previously prepared solution of sodium n-propylate, keeping the temperature of the reaction medium at 50°-55°C by gentle external cooling. 

Monomers have been prepared in benzene solvent by Knoevanagel reaction between 4-vinyl benzaldehyde and malonic derivatives at room temperature, by use of two catalysts chosen according to the nature of compounds (Table I). For carboxylic acids as malonic or cyanacetic acids piperidine can be used for esters as ethylmalo-nate or ethyl cyanacetate piperidinium benzoate is prefered. 

Beilstein Handbook Reference) Acetic acid, cyano-, ethyl ester AI3-19027 BRN 0605871 Cyanacetate ethyle Cyanoacetic acid ethyl ester Cyanoacetic ester EINECS 203-309-0 Estere cianoacetico Ethyl cyanacetate Ethyl cyanoacetate Ethyl cyanoethanoate Ethylester kyseliny kyanoctove HSDB 2769 Malonic acid ethyl ester nitrile NSC 8844 UN2666 USAF KF-25. Liquid mp = -22.5° bp = 205° d = 1.0654 very soluble in EtOH, Et20. 

Similarly Klotzer [24-26] has used the same two ethers of hydroxyurea for the preparation of iV-alkoxy and A-hydroxy derivatives of uracil, barbituric acid, cytosine, thymine, and 5-fluorouracil by condensation reactions catalyzed with sodium ethoxide. Thus, for example, the reaction of N-benzyloxyurea with ethyl cyanacetate gave l-benzyloxy-6-aminouracil which was debenzylated by heating it with hydrogen bromide in acetic acid [24]. In syntheses of 1- and 3-hydroxycytosine [24] and of l-hydroxy-5-fluorouracil the O-benzyl protective group was removed by hydrogenolysis in presence of palladium [25, 26]. 

To 1 to 5 mi of ethanolic solution containing 0 4 to 0 8 mg of the quinone, add 3 ml of a mixture of equal volumes of 95 per cent ethanol and strong ammonia solution. Add 3 to 5 drops of ethyl cyanacetate and allow the mixture to stand for exactly half a minute. Add 5 ml of 6N potassium hydroxide, mix, and leave for fifteen minutes, preferably out of direct sunlight. Dilute to 50 ml and measure the extinction at 445 mjLt, Read off the quantity of quinone from a previously prepared graph. 

Cyanacetic ester. Ethyl chloroacetate is dissolved in ethanol and boiled under reflux, with an alcoholic solution of potassium cyanide. The mixture is then filtered hot from resulting potassium chloride and the alcohol is distilled from the filtrate. The resulting residual ester is purified by crystallization or distillation. Bp 207°... 

Dipropyl acetic acid or valproic acid may be prepared the next way. Propylbromide is mixed with cyanacetic acid in the presence of sodium ethylate, made from absolute ethanol and sodium. By that prepared a,a-dipropylcyanacetic acid ethyl ester is saponified with equimolecular amounts of NaOH to give dipropylacetonitril. The desired dipropylacetic acid is produced by saponification of dipropylacetonitryl with aquatic NaOH. It is colorless liquid. BP 219°-220°C. 

SYNS CYANACETATE ETHYLE (GERMAN) CYANOACETIC ACID ETHYL ESTER CYANOACETIC ESTER ESTERE CIANOACETICO ETHYL CYANOACETATE ETHYL CYANOETHANOATE ETHYLESTER KYSEUNY KYANOCTOVE MALONIC ACID ETHYL ESTER NITRILE USAF KF-25... 

---