152 OXYCAPEOIC ACIDS. 



with water. Large, colorless, very easily soluble plates. 

 Fusing point, 80. Sublimes even below 100. 



2. Isoxy valeric acid (Ethometh oxalic acid). The 

 ether, boiling at 165, is produced by heating ethyl 

 oxalate with a mixture of methyl iodide and ethyl 

 iodide and zinc, and afterwards treating the product 

 with water. The free acid, separated from the ether, 

 forms colorless, easily soluble crystals, fusing at 63. 



5. Oxycaproic Acids. 



- 



1, Leucic Acid. Is produced by the action of 

 nitrous acid on leucine (p. 98). Colorless, easily solu- 

 ble needles ; fusing point, 73. 



2. Isoleucic acid. (Diethoxalic acid). Is obtained, 

 like isoxyvaleric acid, by heating ethyl oxalate with 

 ethyl iodide and zinc. Colorless, easily soluble crys- 

 tals ; fusing point, 74.5 ; sublimes at 50. "When care- 

 fully oxidized it gives propione (p. 110) ; also yields 

 propione, together with ethylcrotonic acid (p. 125), 

 when heated with concentrated hydrochloric acid. 



C. BIBASIC, DIATOMIC ACIDS, C n H 2n ~ 2 4 . 



The acids of this series are derived from the hydro- 

 carbons of the marsh gas series by the replacement of 

 two hydrogen atoms in the latter by two carboxyl 

 groups ; or from the fatty acids by the replacement of 

 one hydrogen atom by the carboxyl group CO. OH. 

 They are produced by the complete oxidation of the 

 primary diatomic alcohols containing twice the group 

 CH 2 .OH ; by heating the dicyan-substitution-products 

 of the marsh gas hydrocarbons (cyanides of the hydro- 

 carbons CH 2W ) and the monocyan-substitution-products 

 of the fatty acids with caustic potassa. 



