Phenylethylbarbituric acid phenobarbitone

Phenylethylbarbituric acid (also termed luminal and phenobarbitone) may be prepared by condensing ethyl phenyletUylmalonate with urea in the presence of sodium methoxide  

The ethyl phenylethylmaloiiate may be obtained from ethyl pheuylacetate by the following series of reactions  

Etbyl pbenylnialonate. In a I-litie flask, equipped with a dropping funnel, mercury-sealed stirrer and reflux condenser, pl oe 11-5 g. of clean sodium pieces (see Section III,7, Note I) add 250 ml. of superdry ethyl alcohol (Section 11,47,5) and allow the vigorous reaction to 

Ethyl phenylethylmalonate. In a dry 500 ml. round-bottomed flask, fitted with a reflux condenser and guard tube, prepare a solution of sodium ethoxide from 7 0 g. of clean sodium and 150 ml. of super dry ethyl alcohol in the usual manner add 1 5 ml. of pure ethyl acetate (dried over anhydrous calcium sulphate) to the solution at 60° and maintain this temperature for 30 minutes. Meanwhile equip a 1 litre threenecked flask with a dropping funnel, a mercury-sealed mechanical stirrer and a double surface reflux condenser the apparatus must be perfectly dry and guard tubes should be inserted in the funnel and condenser respectively. Place a mixture of 74 g. of ethyl phenylmalonate and 60 g. of ethyl iodide in the flask. Heat the apparatus in a bath at 80° and add the sodium ethoxide solution, with stirring, at such a rate that a drop of the reaction mixture when mixed with a drop of phenolphthalein indieator is never more than faintly pink. The addition occupies 2-2 -5 hoius continue the stirring for a fiuther 1 hour at 80°. Allow the flask to cool, equip it for distillation under reduced pressure (water pump) and distil off the alcohol. Add 100 ml. of water to the residue in the flask and extract the ester with three 100 ml. portions of benzene. Dry the combined extracts with anhydrous magnesium sulphate, distil off the benzene at atmospheric pressure and the residue under diminished pressure. C ollect the ethyl phenylethylmalonate at 159-160°/8 mm. The yield is 72 g. 

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SYNS 5-ETHYL-5-PHENYLBARBITUR1C ACID SODIUM 5-ETHYX-5-PHENYLBARBITURIC ACID SODIUM SALT 5-ETHYL-5-PHENYL-2,4,6-(1 H,3H,5H)PYRIMIDINETRIONE MONOSODIUM SALT GARDENAL SODIUM LUMINAL SODIUM PBS PHENEMALUM PHENOBAL SODIUM PHENOBARBITAL ELIXIR PHENOBARBITAL Na D PHENOBARBITAL SODIUM PHENOBARBITAL SODIUM SALT PHENOBARBITONE SODIUM PHENOBARBITONE SODIUM SALT PHENYLETHYL-BARBITURIC ACID, SODIUM SALT SODIUM-5-ETHYL-5-PHENYLBARBITURATE SODIUM PHENOBARBITAL SODIUM PHENOBARBITONE SODIUM PHENYLETHYLBARBITURATE SODIUM PHENYLETHYLMALONYLUREA SOL PHENOBARBITAL SOL PHENOBARBITONE SOLUBLE PHENOBARBITAL SOLUBLE PHENOBARBITONE... 

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