1872.] 



for producing Amides and Nitrites. 



63 



This is the characteristic behaviour of carbonic oxysulphide, which was 

 further identified by its odour, great density, and inflammability. 



The principal reaction that takes place when acetic acid is treated with 

 potassium sulphocyanate accordingly is as follows : — 



(1) KCNS + O, H3 O . OH=C 2 H 3 O . OK 4- HONS, 



(2) HCNS + C 2 H 3 O . OH=C 2 H 3 O . JN T H 2 -f COS. 



The sulphuretted hydrogen and carbonic anhydride, produced simulta- 

 neously with the carbonic oxysulphide, are the complements of a second 

 reaction, the principal product of which I have no doubt is acetonitrile : 



HONS + C 2 H 3 . OH= C 2 H 3 N + H 2 S + C0 2 . 



I must remark, however, that I have not actually proved the formation 

 of this body by experiment. My investigations in the acetic series were 

 completed before this phase of the reaction was thoroughly understood ; 

 and thus probably, owing to its low boiling-point (77°), the acetonitrile 

 had been carried off with the stream of disengaged gases, and had escaped 

 detection. I have not repeated the experiment, because in other series it 

 has been easy to demonstrate the formation of the nitrile. 



Action of Isobutyric Acid on Potassium Sulphocyanate* 



If potassium sulphocyanate be heated with isobutyric acid (which may 

 now be readily obtained in a state of purity by oxidation of isobutylic 

 alcohol separated from fusel-oil), the salt melts under the acid to an oily 

 layer, from the surface of which bubbles of gas are plentifully disen- 

 gaged, consisting, as in the preceding case, of carbonic oxysulphide, 

 carbonic anhydride, and sulphuretted hydrogen. In consequence of 

 the higher boiling-point of isobutyric acid (154°), the reaction proceeds 

 more rapidly than with acetic acid. If the mixture be submitted 

 to distillation when all disengagement of gas has ceased, it begins boiling 

 a few degrees above 100°, the thermometer rapidly rising to 216°; 

 during this time an aromatic liquid passes over, possessing the odour of 

 butyric acid. 



Between 216° and 220° the thermometer remains tolerably stationary, 

 the distillate solidifying in the receiver to a white crystalline mass. On 

 fractionating the Kquid portion passing over before 200°, no product can 

 be obtained showing a constant boiling-point ; but on treating it with a 

 solution of caustic soda, an oily aromatic liquid of characteristic odour floats 

 on the surface, which, separated by a tap-funnel and dried over calcium 

 chloride, boils constantly between 107° and 108°. Its composition and 

 reactions characterize this substance as isobutyronitrile : 



H-C=(CH 3 ) 2 

 C.H 7 K"= 1 

 CN 



VOI. XXI. 



F 



