MM. Wurtz and Friedel on Lactic Acid. 301 



and Friedel have found that it is also obtained by heating lactic 

 acid with alcohol in closed vessels to a temperature of 170°. 

 The former of these compounds is a true acid, and readily 

 forms salts. When monoethylic lactate, as the latter compound 

 is called, is treated with potassium, hydrogen is disengaged, and a 

 compound is obtained isomeric with ethylactate of potash, and 

 which, when treated with iodide of ethyle, forms dilactic ether. 



These two ethers present a most curious example of isomerism. 

 They are formed by the same acid, both contain the same group 

 ethyle, and yet one of them is an energetic acid, while the other 

 is perfectly neutral. This is accounted for by the different parts 

 that the two atoms play in lactic acid. One of them is strongly 

 basic, and can be replaced by a metal or by an organic group, 

 such as ethyle ; in both cases a neutral compound is obtained. 

 The other atom can be easily replaced by oxygen groups, such 

 as the radicals of monobasic acids. If replaced by an indifferent 

 group, such as ethyle, it is still acid, because the atom of basic 

 hydrogen has not been touched. 



The authors have noted similar isomeric relations between 

 lactamethane, G 5 H U NG 2 , and a new amide produced by the 

 action of ethylamine on lactide, G 3 H 4 G 2 . By potash they un- 

 dergo a different decomposition — the latter into lactic acid and 

 ethylamine, and the former into ammonia and ethylactic acid. 



Lactyle, the radical of lactic acid, has the property of multi- 

 plying itself in one and the same body so as to form compounds- 

 which may be referred to condensed types analogous to the 

 polyethylenic compounds. 



Dilactic Ether. — When chlorolactic ether* acts upon lactate of 

 potash, chloride of potassium is formed, and a dilactic ether, 

 according to the equation 



€ 5 IP O 2 CI -f G 3 II 5 K G 3 = K Cl-f G 8 II 14 O 5 . 



Chlorolactic Lactate of New body, 



ether. potassium. 



The formula of the new body, monoethylic dilactate, may be 



(G 3 H 4 G") 2 "!••■■ 

 written thus/ (ri<2ii5\\i r^ 3. Besides this there is another lactic 



(G 3 II 4 G') 2 1 

 ether, diethylic dilactate, v ,^ 2 tt 5 o fO 3 , obtained by the action 



of chlorolactic ether on ethylolactate of potassium. These com- 

 pounds are the ethers of the anhydrous lactic acid of Pelouze, 

 and can be regarded as containing two equivalents of the radical 



G 3 II 4 0" ] 

 lactyle according to the formula G 3 1I 4 0" >G 3 . There is a lac- 



HRJ 



* Phil. Mag. vol. xviii. p. 287. 



