DiPhenyl arsenic acid chloroarsine

The mixture is stirred continuously and maintained for 3 hours at 15° C., when sodium phenyl arsenate is formed. This is neutralised with hydrochloric acid and filtered through a press in order to separate resinous substances which are formed. The phenyl arsenic acid in the filtrate is reduced to phenyl arsenious oxide by passing a current of sulphur dioxide through. A heavy oil deposits at the bottom of the vessel and this is removed by decantation and redissolved in 40° B. sodium hydroxide solution. After diluting with 8 cu. m. of water, the solution is cooled to 15° C. and run slowly into another solution of diazobenzene chloride prepared as before. The sodium salt of diphenyl arsenic acid which is formed is slightly acidified with hydrochloric acid, the diphenyl arsenic acid filtered off and redissolved in 20° B6. hydrochloric acid (i part of the arsenic acid requires 3 parts of hydrochloric acid) and the solution obtained is then run into an iron vessel, lined internally with tiles. Sulphur dioxide is then passed through for 8 hours while the temperature is maintained at about 80° C. Diphenyl chloroarsine then separates as an oil which forms a layer at the bottom of the vessel. It is separated off and dried in vacuo. 

Chhrosidphoitic Acid. Diphenyl chloroarsine, on treatment with chlorosulphonic acid forms, besides benzene sulphonyl chloride, a chloride of diphenyl arsenic acid having the formula (CjH5)2AsOOH.HC1, which forms prisms and melts at 130° C. 

Fluorosulphonic Acid. This converts diphenyl chloroarsine into benzene sulphonyl fluoride and the sulphate of diphenyl arsenic acid, 2(CgH5)2As00H.H3S04, melting at 117° C. 

Chloramine-T. Diphenyl chloroarsine reacts with chloramine-T in presence of water to form diphenyl arsenic acid, which consists of needles melting at 175° C. (see p. 311). 

Hydrochloric Acid. On boiling diphenyl chloroarsine with hydrochloric acid, arsenic trichloride and triphenyl arsine are formed, as follows ... 

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