TRANSFORMATION OF NITROAMINES AND ALLIED SUBSTANCES. 95 



concentration of the complex must vary greatly ; the speed of the trans- 

 formation of the complex into chloroanilides must depend not -only on 

 the constitution of the anilide hut also on the constitution of the 

 medium. 



To avoid such a number of arbitrary assumptions it seems at least 

 simpler to regard chlorination as occurring directly and not by way of 

 such a complex. 



The Velocity of Chlorination of Anilides. 1 (With Harold King, M.Sc.) 

 I The speed of the chlorination of anilides is being investigated with 

 the object of ascertaining the effect of the nature, the number, and the 

 position of various substituents, and the effect of acyl groups on the 

 reaction. 



Owing to the simultaneous formation of chloroamines, ArNCTAc 

 and C-chloro-derivatives, ClArNH'Ac, in dilute acetic acids, it is 

 obviously simplest to measure the speed of the formation of the latter, 

 in glacial acetic acid, when the former does not occur. 



In glacial acetic acid, the reaction of chlorine and anilide is of the 

 second order. It appears to be quite simple in character ; no disturbing 

 side reactions are observed, and the values of the velocity coefficients 

 are remarkably constant throughout the reaction. 



As the change proceeds hydrogen chloride appears in the solution. 

 Control experiments have shown that even when as much as 8-gram 

 molecular proportions of the acid are added, the velocity of chlorination 

 is not affected. This fact offers a marked contrast to bromine in the 

 presence of hydrogen bromide. Addition of hydrogen bromide arrests 

 the bromination of anilides owing to the formation of hydrogen per- 

 bromide, HBr 3 (compare Report 1910). 



The following table gives the value of the velocity coefficient, k", 

 temperature 16°, concentrations in gram molecules per litre, and time 

 in minutes : — 



Formanilide 

 Acetanilide 

 Propionanilide • 

 Butyranilide 

 i'soValeranilide 

 Stearanilide 

 Oxanilide 

 Benzanilide 

 Aceto-o-anisidide 

 Aceto-p- anisidido 

 Aceto-o- phenetididc 

 Aceto- p- phenetidido 



4 95 

 40 



72 



04-5 



57 



lit 



2 



42 



60 



57 



90 



85 



Relation between the Nature of the Acyl Groups, and the Proportion 

 of Oirtho- and Para-Chloro-derivatives formed in chlorinating Acyl- 

 anilides. 2 (With Harold King.) 



We have extended the experiments begun by Mr. W. J. Jones 3 on 

 the estimation of the proportion of o- and p-chloro-derivatives which are 



1 Trans. Chem. Hoc, 1911, 99, 1369. 



3 Ibid., 1909, 95, 1056. 



'-Ibid., 1911, 99, 1377. 



