Antimony, organometallic compounds

G. O. Doak and L. D. Freedman, Organometallic Compounds of Arsenic, Antimony, and Bismuth,]ohn Wiley Sons, Inc., New York, 1970. 

Mercury, tin, lead, arsenic, and antimony form toxic lipophilic organometallic compounds, which have a potential for bioaccumulation/bioconcentration in food chains. Apart from anthropogenic organometallic compounds, methyl derivatives of mercury and arsenic are biosynthesized from inorganic precursors in the natural environment. 

There are many organometallic compounds of arsenic, antimony, and bismuth known that constitute series having chemical properties that differ markedly. These compounds generally decrease in stability in the order As > Sb > Bi, which agrees with the increasing difference in size of the atoms and carbon atoms. Arsenic compounds include both aliphatic derivatives and heterocycles such as arsabenzene,... 

The application of these techniques has led to the discovery of a number of organometallic species of arsenic, tin, and antimony in the marine environment. Germanium has not been observed to form organometallic compounds in nature. Some aspects of the geochemical cycles of these elements which have been elucidated by the use of these methods are discussed. 

It is now well established that organometallic compounds are formed in the environment from mercury, arsenic, selenium, tellurium and tin and hence were also deduced on the basis of analytical evidence for lead, germanium, antimony and thallium. Biological methylation of tin has been demonstrated by the use of experimental organisms. Methylgermanium and methyllead were widely found in the environment but it is debatable whether germanium and lead are directly methylated by biological activity in natural environment. 

As was the case with the volume The chemistry of organic arsenic, antimony and bismuth compounds, published in 1994, it was clear that the set of five volumes describing organometallic compounds (edited by Professor Frank R. Hartley) did not deal in sufficient depth with organic compounds of germanium, tin and lead. Hence we decided to publish the present volume, which we hope will be a useful and worthwhile addition to the series The Chemistry of Functional Groups. In this volume the authors literature search extended in most cases up to the end of 1994. 

The one exception is the capacity of some micro-organisms to methylate certain metals, e.g. arsenic, antimony and mercury, probably as a kind of detoxification mechanism. Methylcobal-amin is the only organometallic compound known to have a physiological function in life processes. 

Doak, G. O., Freedman, L. D. Organometallic compounds of arsenic, antimony and bismuth, Wiley Interscience, 1970... 

Recently, it was found that organometallic compounds, such as silicon (equation tin (eqnation 8), antimony (eqnation 9), and lead (eqnation 10), instead of organic halides, react with olefins to produce the same products as obtained by the MH reaction. 

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