Arsine derivatives mercury

Methane bacteria have been shown to catalyze reactions in which the active methyl group is transferred to acceptors such as arsenate or mercury. When extracts are incubated in a hydrogen atmosphere with methylcobalamin, arsenate, and ATP, a volatile arsine derivative is formed (20). Arsines are difficult and dangerous to work with they are extremely poisonous and are oxidized rapidly in air. Fortunately they have an intense garhc odor so the investigator is warned of their presence. 

The oldest method, and one which gives good results, consists in heating together mercury diarjds and arsenious chloride or aryldi-chloroarsines. The latter derivatives are useful when mixed aryl-arsines are desired ... 

This derivative is obtained in a similar manner to the preceding one, from 3 5-diacetylamino-4-hydroxyphenylarsinic acid, the product being purified by solution in alkali and precipitation with dilute hydrochloric acid. In this ease, however, the reaction requires thirty days for completion. The mercurated arsinic acid melts at 234° C., and gives clear solutions in aqueous sodium carbonate, caustic alkalis, and ammonia, the latter solution when boiled with ammonium sulphide yielding mercury sulphide. The position of the mercury is ascertained by converting the compound into 2-iodo-3 5-dia-cetylamim-4s-hydroxyphenyU arsinic add. 

Derivation Condensation of arsenic trichloride with acetylene in the presence of aluminum, copper, or mercury chloride. The mixed arsines are separated by fractionating. 

When iodoarsines are coupled with fluorocarbon iodides in the presence of mercury, arsines and not arsonium derivatives are produced (67-70). 

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