454 
MR. G. B. BUCKTON AND DR. A. W. HOFMANN’S RESEARCHES ON THE 
method of procuring the nitrile of the methyl-series in quantity and in a state of 
purity. 
Preparation of Acetonitrile. 
The preparation of cyanide of methyl (acetonitrile), by decomposing sulphomethy- 
late of potassium with cyanide of potassium, is unsatisfactory, both as to quantity and 
quality of the product obtained. The presence of a minute amount of moisture 
in the materials employed gives rise to a number of secondary products, the chief 
of which are, cyanide and carbonate of ammonium, and a gas possessing a highly 
offensive odour, which imparts to the distillate a smell not at all due to the nitrile 
itself. By far the most advantageous method of preparing acetonitrile consists in 
acting upon acetamide with anhydrous phosphoric acid, as proposed by M. Dumas. 
Acetic ether is not immediately soluble in a moderate quantity of aqueous ammo- 
nia ; but after five or six hours’ contact, the layers at first formed disappear, and the 
liquid becomes homogeneous. 
If distillation be now at once commenced, scarcely a trace of acetamide will be 
obtained. The change, on the other hand, is complete if the mixture be exposed for 
some hours to a temperature of 120° or 130° C, 
We have employed in this operation a wrought-iron cylinder, similar to that used 
by Dr. Frankland in his researches, which had been constructed for us by Mr. James 
Nasmyth, who never fails most kindly and liberally to lend the extraordinary 
resources of his celebrated establishment for scientific purposes. Equal volumes of 
acetic ether and concentrated ammonia were introduced into the boiler, the brass valve 
of which was protected from corrosion by a steel screw and leaden washer. After six 
hours’ digestion the acetamide was separated by distillation with the thermometer 
from the alcohol formed, that part only being reserved as anhydrous which had 
passed over above 200°. When acetamide is intimately mixed with about an equal 
volume of anhydrous phosphoric acid in a retort, a powerful action commences im- 
mediately, and the nitrile passes over colourless, but contaminated with acetic and 
hydrocyanic acids. Towards the end of the operation it is necessary to use a strong 
heat to drive off the last portions. The distillate is now agitated with just sufficient 
aqueous potash to neutralize the acids, when the nitrile floats on the surface, and 
may be removed for rectification over a fresh quantity of phosphoric acid, to render 
it perfectly anhydrous. Pure acetonitrile possesses an ethereal odour, faintly recall- 
ing that of cyanogen ; its aromatic taste is pungent, but not disagreeable. We 
observed the boiling-point 77°-78°, which coincides with that observed by Dumas. 
It does not appear to have been pi’eviously noticed, that acetonitrile burns with a 
luminous flame, the edges of which are beautifully tinged with peach-blossom colour. 
The flame and odour of acetonitrile unmistakeably bespeak the cyanic relations of 
this compound. 
