Organoarsenics

Primary and Secondary Arsines. Compared to the vast number of known organoarsenic compounds, relatively few primary (RASH2) and secondary (R2ASH) arsines have been described. Primary arsines are commonly prepared by the 2inc—hydrochloric acid reduction of substances containing... 

Cyclic and Polymeric Substances Containing Arsenic—Arsenic Bonds. A number of organoarsenic compounds containing rings of four, five, or six arsenic atoms have been prepared (cycHc polyarsines). The first such four-membered ring compound to be adequately characterized, tetrakis (trifluoromethyl) tetrarsetane [7547-15-17, was obtained by the interaction of a diiodoarsine and mercury (107,108) ... 

Inorganic ar senic normally occurs in two oxidation states As(V) and As(III). Arsenic (V) gives a significantly lower response than ar senic (III). For pre-reduction As(V) to the As(III) concentrated hydrochloric acid and potassium iodide/ascorbic acid reagents were used. As organoarsenic compounds do not react with sodium tetrahydi oborate, they were decomposed with a mixture of HNO and on a hot plate. 

More extensive catenation occurs in the cyc/o-polyarsanes (RAs) which can readily be prepared from organoarsenic dihalides or from arsonic acids as follows ... 

In general As " organic derivatives are more toxic than As derivatives. The use of organoarsenicals in medicine dates from the discovery in 1905 by H. W. Thomas that atoxyl (first made by A. Bechamp in 1863) cured experimental trypanosomiasis (e.g. sleeping sickness). In 1907 P. Erlich and A. Bertheim showed that atoxyl was sodium hydrogen 4-aminophenylarsonate... 

Organoarsenic compounds have been of importance in human toxicology but have not as yet received much attention in regard to environmental effects. Like methyl mercury compounds, they are both synthesized in the environment from inorganic forms and released into the environment as a consequence of human activity (Environmental Health Criteria 18). They can cause neurotoxicity. 

Significant quantities of organoarsenic compounds have been found in marine organisms, and questions have been asked about the possible health risk to humans consuming sea food. 

An inductively coupled plasma formed by passing argon through a quartz torch is widely used for the mass spectroscopic analysis of metal compounds separated by online HPLC.6 Samples are nebulized on introduction into the interface. Plasma impact evaporates solvent, and atomizes and ionizes the analyte. Applications include separation of organoarsenic compounds on ion-pairing F4PLC and vanadium species on cation exchange. 

Organic solvents Organo(alkyl)mercury Organoarsenicals Ozone... 

Many organoarsenic compounds are prepared by reactions of AsC13 with alkyl group transfer agents such as Grignard reagents, lithium alkyls, or aluminum alkyls. Typical reactions include... 

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