2!>4 Drushel and Dean — Hydrolysis of Esters of 



Preparation of the Esters. — The preparation of these esters 

 was attended with some difficulty, largely due to the impossi- 

 bility of employing any very effective methods of purification. 

 The glycollic and methvloxv esters in particular are very 

 soluble, rendering it impracticable to wash them with water. 

 The last two esters of the series are more satisfactory in their 

 preparation, although small yields were obtained by the 

 methods employed. 



The glycollic ester was prepared according to the method of 

 Schreiner,* which depends upon heating together sodium 

 glycollate, ethyl chloracetate and absolute alcohol in a sealed 

 tube at 150° to 160° for a day. The tubes were then opened 

 and the ester purified by fractional distillation. The first 

 attempts to prepare glycollic ester by this method proved 

 unsuccessful. There seemed to be a great tendency on the 

 part of the ester to break down into glycollic acid and this 

 was very difficult to remove, although its boiling point is 30° 

 above that of the ester. The presence of small quantities of 

 water or free acid in the glycollate appears to prevent almost 

 entirely the formation of the ester. By the use of absolutely 

 neutral and carefully dried sodium glycollate we were able to 

 prepare a small quantity of the ester, which boiled at a con- 

 stant temperature of about 155° and was proven free of 

 halogen. The boiling point given in the literature is 160°, 

 but the fractions we obtained boiling at this temperature gen- 

 erally contained free acid. It does not seem probable, how- 

 ever, that the presence of traces of glycollic acid can noticeably, 

 affect the hydrolysis, as it is one of the products formed in the 

 reaction and is a very weak acid. 



The alkyloxy acetic esters were all prepared by the same 

 general method, the action of sodium alcoholate on ethyl chlor- 

 acetate. The reaction proceeds according to the following 

 equation : 



CH,Cl.COOC s H 5 + NaOR -> CH 2 OR.COOC,H 6 + NaCl. 

 Iu one case the mixture was allowed to react in ethereal solution, 

 in the others an excess of absolute alcohol was used. The yields 

 were rather poor, varying from 30 per cent to 35 per cent in 

 the different cases. It seems possible that this may have been 

 due to loss of ester while the excess of alcohol or ether was 

 being distilled off, as the reaction is one which should go to 

 completion. 



The boiling points of the esters are given as follows : ethyl 

 glycollate, 160° ; ethyl methyloxy-acetate, 130° ; ethyl ethyl- 

 oxy-acetate, 152°, and ethyl propyloxy-acetate, 184r - 5°. The 

 solubilities are not given in the literature. All but the propyl- 

 oxy ester seem to be very soluble ; the latter dissolves with a 

 little difficulty in the quantities used in the hydrolysis. 

 *Ann. d. Chem. u. Phartn., cxcvii, 5. 



