SCIENTIFIC PROCEEDINGS 



Abstracts of Communications. 

 Ninety-fourth meeting. 



New York Post-Graduaie Medical School. 

 President Gies in the chair. 



8 (1383) 



A simple method for making p-arsanilic acid. 



By Philip Adolph Kober and Walter S. Davis. 



[From the Division of Laboratories and Research, New York State 

 Department of Health, Albany, N. Y.] 



The preparation of what is now known as primary arsanilic 

 acid, the starting point and the basis of Ehrlich's synthesis of 

 salvarsan, was first mentioned by Bechamp 1 in 1863. In spite of 

 Bechamp's published work, and that of many others, the fact 

 remains that the literature does not contain definite directions for 

 making the primary arsanilic acid. Many laboratories have spent 

 much effort, money and time in trying to evolve the synthesis 

 from the general directions given in the literature, but without 

 much success. The process in its highest form is generally under- 

 stood to be a trade secret. 



Without going into details, it can be shown that the directions 

 either call for too much aniline or too high a temperature, or both. 

 By controlling one or both of these factors one can obtain the 

 primary free from secondary in large yields, practically pure, with 

 ease. 



One thousand c.c. of crude arsenic acid (75 per cent.) are 

 heated in an open beaker or vessel, at 120 0 to 140 0 C. for 12 to 15 

 hours by means of an oil or "Crisco" bath. This should con- 

 centrate the acid to practically 100 per cent. 



1 Compt. rend., LVI., 1172, 1863. 



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