OF SUCCINIC AND PYEOTAETAEIC ACIDS. 
65 
We are now enabled, thanks to the researches of Messrs, Peekin and Duppa, and of 
M, Kekule*, to build up three highly complex organic acids (succinic, paratartaric, and 
malic) from a simple hydrocarbon ; and what is more important, we are enabled to do 
this by processes, every stage of which is perfectly intelligible. 
The question now arises. Is the foregoing reaction capable of general application 1 
Can the homologues of succinic acid be obtained in a similar manner % With the view 
of determining this point, I have endeavoured to prepare pyrotartaric acid from the 
cyanide of propylene, the radical of propylglycol. 
Preparation of Cyanide of Propylene. 
This body, which forms the first step in my process for pyrotartaric acid, I succeeded 
in obtaining in the following manner: — A mixture of one equivalent of bromide of 
propylene and two of cyanide of potassium, together with a considerable quantity of 
alcohol, was exposed to the temperature of a water-bath in well-corked soda-water- 
bottles for about sixteen hours. Their contents were then filtered, and the alcohol 
distilled off the filtered liquor. A liquid residue was thus obtained, which was very 
black, and by no means of a promising appearance. This was filtered at 100° Cent., 
and digested with ether, which left a large quantity of a black tarry matter undissolved. 
The residue obtained on evaporating the etherial solution was then submitted to distilla- 
tion. Almost the entire liquid passed over between 265° and 290° Cent. The fraction 
distilling between 277° and 290° was analysed and gave the following numbers: — 
Theory. 
Experiment. 
Cjo • 
. 60-00 
per cent. 
63-82 
I. II. 
61-95 
H, . . 
. 6-00 
6-38 
6-54 
N, . . 
. 28-00 
29-80 
29-49 
94-00 
100-00 
I do not think it possible to obtain this body in a state of greater purity, unless by 
fractional distillation in vacuo, since it suffers partial decomposition when distilled in 
air, as evidenced by a slight evolution of ammonia during the process. 
The properties of this cyanide very much resemble those of the preceding. It differs 
however in its physical state, which is that of a liquid at the ordinary temperature of 
the air. It is soluble in water, alcohol, and ether. It has an acrid taste. It is colour- 
less and neutral to test-paper. It is decomposed with great facility by potassium, 
cyanide of potassium being formed in large quantity. Its solution in water gives no 
precipitate with nitrate of silver. Heated with potash, an acid is formed, and ammonia 
evolved. 
* Quarterly Journal of the Chemical Society, July 1860; and Bulletin de la Societe Chimique de Paris, 
10 Aout 1860, p. 208. 
