BARTOW AND MCFARLAND : LIQUID AMMONIA. 85 



CONCLUSION. 



The few acid chlorids tried, except bromacetylchlorid, gave amids. 

 In our experiments with chlorids and liquid ammonia, we have pre- 

 pared the amids of the three chloracetic acids and benzamid. Mr. 

 O. F. Stafford has prepared sulfamid. 



A few esters, especially the chloracetic ethyl esters, gave better re- 

 sults in forming amids, and the operation was more easily carried out 

 than with the corresponding chlorids. We have, by the addition of 

 esters to liquid ammonia, prepared the amids of the three chloracetic 

 acids, of dibromacetic acid, cyanacetic acid, chlorpropionic acid, 

 pelargonic acid, oxalic acid, and tartaric acid. Malonic acid amid was 

 formed only at a higher temperature. 



A few esters gave substances whose melting-points varied from 

 those of expected amids found recorded in chemical literature. 



Many of the esters tried have given no well-crystallized amids un- 

 der the conditions which prevailed in these experiments. The causes 

 for this may be conjectured : First, the low temperature of the reac- 

 tion, as shown in the case of malonamid, which was not formed at the 

 temperature of boiling ammonia, but which form in a sealed tube at 

 the temperature of the room ; second, the short time for the reaction 

 allowed by the evaporation of ammonia from open vessels ; third, the 

 reaction of ammonia on esters is reversible, and is even prevented by 

 excess of alcohol (Bonz, Ph. Ch. 8, 900). 



We hope to carry our experiments farther, to identify the rest of 

 the substances obtained, and to study the action of liquid ammonia 

 on the esters at higher temperatures and in the presence of diluting 

 media, such as ether and benzene. 



