W. A. Drushel — Substituted Aliphatic Acids. 515 



of the monoalkylated and dialkylated esters in alcoholic 

 solution and separated sodium iodide with a small excess 

 of alkyl iodide, became neutral to litmus. The mixture 

 in each case was found to contain a large amount of the mono- 

 alkylated ester with a relatively small per cent of the dialky- 

 lated ester. The esters resulting from the introduction of the 

 homologues of the methyl group were separated by the differ- 

 ence in the solubilities of the mono- and dialkylated esters in 

 cold 10 per cent sodium hydroxide solution, the monoalkylated 

 ester being readily soluble (with saponification) while the di- 

 alkylated ester is not appreciably attacked by cold dilute 

 sodium hydroxide even when in contact with this reagent for 

 several hours. After separation of the dialkylated ester the 

 mouoalkylated acid was recovered from the sodium salt and 

 esterified. 



(b) /3-Cyan substituted fatty acid esters.— It was found pos- 

 sible to prepare ethyl beta cyan propionate with an unsatisfac- 

 tory yield from beta ioclopropionic ester by a modification of 

 Zelinsky's- method for the preparation of the corresponding 

 alpha ester. One equivalent of finely powdered potassium 

 cyanide was added to ethyl beta iodopropionate dissolved in 

 absolute alcohol and heated at 100° in a sealed tube. A small 

 yield of ethyl beta cyan propionate entirely free from iodine 

 and boiling at 110° under a pressure of 12 mm was obtained 

 which was used in the hydrolysis experiments. 



For the preparation of ethyl beta cyanbutyratemalonic ester 

 was used as the starting out material. Malonic ester was first 

 converted into ethylidene malonic ester by the method of 

 Komnenos,f and from this ethyl beta cyanbutyrate was pre- 

 pared by the method of Bredt and Kallen.;}: One mol of 

 malonic ester was condensed with one mol of acetaldehyde in 

 the presence of one and a half mols of acetic anhydride by 

 heating in a sealed tube at 100° for two days. The condensa- 

 tion was made according to the following reaction, obtaining a 

 somewhat less than fifty per cent vield : CH 3 CHO + CH„- 

 (COOC 2 H 6 ) 2 = CH.CH : C(COOC 2 H;) 2 + H 2 0. The purified 

 ethylidene malonic ester was heated at 60° for seven hours 

 with one equivalent of potassium cyanide, a little water and a 

 large excess of alcohol. The following reaction expresses this 

 step : 



CH 3 CH : C(COOCJBU+ KCN + H 2 = CH 3 CH(CN)CH„- 

 COOC a H 5 + HKCO, + C 2 H 5 0H. The ethyl beta cyanbuty- 

 rate obtained in this way after purification boiled at 110 o -112° 

 under a pressure of 20 mm , and did not decolorize a dilute 



*Zelinsky, Ber. Dtsch. Chem. Gesellsch, xxi, 3162. 



f Komnenos, Liebig's Ann. Chem. Pharm., ccxviii, 157. 



\ Bredt, Kallen, ibid., ccxciii, 351. 



