Ethyl diethylmalonate

Diethylbarbituric acid. In a dry 250 ml. distilling flask, fitted with a thermometer reaching to within 3-4 cm. of the bottom and a condenser, place 51 g. of clean sodium and add 110 g. (140 ml.) of super-dr ethyl alcohol (Section 11,47,5). When all the sodium has reacted, introduce 20 g. of ethyl diethylmalonate and 7 0 g. of dry imea (dried at 60 for 4 hours). Heat the flask in an oil bath and slowly distil off the ethyl alcohol. As soon as the temperature of the liquid reaches 110-115°, adjust the flame beneath the bath so that the contents of the flask are maintained at this temperature for at least 4 hours. Allow the flask to cool somewhat, add 100 ml. of water and warm until the solid (veronal-sodium) dissolves. Pour the solution into a beaker, and add a further 100 ml. of water but containing 7 0 ml. of concentrated siilplmric acid this will hberate the veronal from the sodium derivative. The veronal usually crystallises out if it does not, add a few more drops of dilute sulphuric acid until the solution is acid to Congo red. Heat the contents of the beaker, with stirring and the addition of more water if necessary, until all the veronal dissolves at the boiling point. Allow the hot solution to cool, filter off the crystals of veronal and diy in the air. The yield is 12 g., m.p. 190°. 

The condensation of 1 mol of ethyl malonate with two mols of ethyl iodide in the presence of two mols of sodium ethoxide gives a good yield of ethyl diethylmalonate. Upon aUowing the latter to react with the theoretic quantity of urea in the presence of an alcoholic solution of sodium ethoxide, veronal (diethylbarbituric acid or diethylmalonylurea) is produced. 

Etbyl-l,5-propanediol or Ethyltrimetbylene-glycol, HO.Ol2.CH(CaHB)-CH mw 104.15 liq, bp 124-7°(l6 mm Hg). Prepd by the lithium aluminum hydride reduction of 2-ethyl diethylmalonate... 

Ethyl diethylmalonate. Equip a 1 litre three-necked flask with a... 

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