( 138 ) 



Chemistry. — ''On the action of ammonia and aniines on ally I 

 formate". By Prof. P. van Romburgh. 



The great ease with which allyl formate is saponified by alkaHs 

 induced me to try whether ammonia, which, as is well-known, acts 

 upon esters of fatty acids but slowly at the ordinary temperature, 

 would not react equally readily on this ester. The result surpassed 

 my expectation. 



If gaseous ammonia is passed into ally! formate still containing 

 a little allyl alcohol, it is rapidly absorbed whilst the liquid gradually 

 becomes so hot, that it is necessarj' to connect the flask with a 

 reflux apparatus in order to prevent loss of ester. If the contents 

 are heated to 120°, when the increase in weight slightly exceeds 

 1 mol. of ammonia to one mol, of ester, the excess of ammonia 

 passes off with the allyl alcohol and if now the residue is distilled 

 in vacuo, a fine yield of formamide is obtained (b.p.io 113"), which, 

 after a single freezing, melts at 2°. 4 ^). 



If, however, dry ammonia is passed into pure allyl formate, 

 hardly any action is noticed in the first hour. The ammonia is but 

 slowly dissolved so that the concentration is only very small, but 

 gradually as the reaction proceeds the gas is more eagerly absorbed 

 and the temperature rises increasingly. 



If, therefore, we wish to prepare in a short time large quantities 

 of formamide by means of this method it is advisable to add to 

 the allyl formate a few percents of allyl alcohol, although this may cause 

 a slight diminution in the limit value '), as happens, generally, in the 

 formation of amides from esters. 



I showed many years ago that allyl formate ma^^ be readily 

 prepared by heating the diformine') of glycerol, obtained from glycerol 

 and oxalic acid. As we can now obtain commercial formic acid of 

 great concentration (99—100 "/J at a very low price, large quan- 



1) Franchimont (Rec. XVI, 137) found the melting point at 3° ; other observers 

 state a lower figure. 



Pure formamide may be distilled by rapid heating without perceptible decompo- 

 sition (b.p. 219°) ; at least with such a preparation I did not succeed in demon- 

 strating the formation of ammonia and carbon monoxide, which are readily obtained 

 from an impure product. 



2) BoNz, Zeitschr. phys. Ghem. II, 865. 



3) I think it is not superfhious to point out that the theory recently defended 

 by Nef (Ann. 335, 230) that the formation of allyl alcohol from glycerol and 

 oxahc acid must be explained by a dissociation of diformine into formic acid and 

 propargyl alcoliol is based on an error. The main product of diformine on heating 

 is allyl ibrmate. 



