Aniline Arsanilic acid

Arsanilic acid was first synthesised, in very poor yield, by melting arsenic acid with aniline ... 

Additional amounts of arsanilic acid may be obtained from the various mother liquors. The products thus obtained are usually rather impure and hence are not considered in the yields quoted. On larger scale production it would be economical to recover this material as well as the excess aniline. 

Arsanilic acid was prepared by Bechamp 1 by heating aniline arsenate to 190-200°. The product was originally described as the anilide of arsenic acid, but Ehrlich and Bertheim 2 showed its structure to be that of a true aryl arsenic acid. 

The feasible methods of preparing arsanilic acid all depend upon the interaction between aniline and arsenic acid. Various temperatures ranging from 150 to 200° and various ratios of aniline to arsenic acid have been recommended.3... 

Detailed procedures for the preparation of arsanilic acid and sodium p-hydroxyphenylarsonate, by arsonation of aniline and phenol, respectively, are published in Organic Syntheses.79> 80... 

SYNS p-AMINOBENZENEARSONIC ACID 4-AMINOBENZENEARSONIC ACID AMINO-PHENYLARSINE ACID p-AMINOPHENYLARSINE ACID p-AMINOPHENYLARSINIC ACID 4-AMINOPHENYLARSONIC ACID p-ANILINE-ARSONIC ACID ANTOXYLIC ACID p-ARSANIL-IC ACID 4-ARSANILIC ACID ATOXYLIC ACID... 

Weston and coworkers determined arsanilic acid and carbarsone in animal feeding stuffs. The additives were extracted from the food with water the carbarsone present was converted to arsanilic acid that was then reduced to aniline, which can be separated by steam distillation and determined by chromatography and a flame ionization detector. 

Arsanilic acid, a drug used to treat Eimeria infection, also serves as a versatile starting material for preparing various organoarsenical drugs. It has been prepared by heating aniline with arsenic acid [26]. 

B hamp 38) obtained a colorless product on heating aniline arsenate with excess aniline. This was subsequently identified as an arsanilic acid. 

When triphenylarsine in xylene is heated with hydrogen (60 atm) benzene and arsenic are produced 267). Raney nickel cleaves tri-(a-naphthyl)arsine and triphenylarsine yielding binaphthyl and biphenyl respectively 265). Nickel-aluminum alloy in aqueous alkali gives aniline from arsanilic acid 268), and sodium amide in boiling piperidine cleaves benzenearsonic acid 269). Phenyl groups are also lost from triphenylarsine when this is irradiated with thermal neutrons 270). 

Sodium anazolene. See Acid blue 92 Sodium aniline arsonate. See Sodium arsanilate... 

---