376 Mr. C. Schorlemmer on the Derivatives of Propane. [Apr. 8, 



chlorine, the chief product of the reaction being a liquid which boils at 

 94°-98° C, and has the formula C 3 H 6 Cl 2 . 



0*1600 gave 0*39/0 silver chloride and 0*005 silver. 



Calculated for C 3 H 6 Cl 2 . Found. 

 62*8 per cent. 01. 62*4 per cent. 



This body is propylene dichloride ; for its boiling-point not only coin- 

 cides with that of this compound, but also all its reactions are the same. 

 Heated with potassium acetate and acetic acid in closed tubes, it is 

 readily decomposed, a high boiling acetate being formed, which, on heat- 

 ing with concentrated potash solution and distilling, yields a liquid the 

 last portion of which boils between 180°-190° C, and possesses the sweet 

 taste of propyl glycol. I did not isolate the glycol in the pure state, but 

 proposed to establish its structure by oxidation. 



A diluted cold solution of chromic acid acts violently on it, carbon 

 dioxide being evolved in abundance, and a strong odour of aldehyde being 

 recognized, which, on further addition of the oxidizing liquid, was changed 

 into that of acetic acid. By distillation an acid liquid was obtained, which, 

 on boiling with silver carbonate, yielded a silver-salt, which crystallized 

 in the well-known needles of silver acetate. 



0*3013 of this salt left on ignition 0*1935 silver. 



Silver acetate contains Found. 

 64 67 per cent Aq. 64*22 per cent. 



The oxidation-products (carbon dioxide and acetic acid) prove suffi- 

 ciently that the structure of the glycol is expressed by the formula 

 CH 3 -CH (Oil)-CH, (OH), which is that of the known propyl glycol. 



The foregoing researches establish a general reaction for converting 

 secondary compounds of the alcohols into those of primary radicals. This 

 is effected by replacing the iodine in secondary iodides by hydrogen, and 

 subjecting the hydrocarbons thus obtained to the action of chlorine, by 

 which the primary chlorides are formed. 



Of greater interest, perhaps, as possessing an important bearing on the 

 theory of substitution, is the fact that the second substitution-product of 

 propane consists of propylene dichloride, having the structure CH 3 — CH 01 

 — CH a 01. This was the less to be expected, as ethane, C 2 H 6 , the hydro- 

 carbon next lower in the series, yields, by acting on it with chlorine as 

 second product, ethylidene dichloride, CH 3 — CH Cl 2 . Whilst, therefore, in 

 propane first one hydrogen atom in the methyl group is replaced by 

 chlorine, and afterwards one which is combined with the adjoining carbon 

 atom, in ethane the substitution takes place at one and the same carbon 

 atom. The action of chlorine upon propane is certainly in contradiction 

 to all theories of substitution which have been expounded. 



In a second communication I propose to describe the higher chlorinated 

 substitution-products of propane. 



