Synthetic Organic Radiochemistry

Astatine, generally speaking, is a difficult isotope to study from a chemical viewpoint because no stable isotopes exist. Although the study of the chemical properties of astatine began over 40 years ago (44), the element s precise behavior is still in doubt. The chemical similarity between astatine and its nearest halogenic neighbor, iodine, is not always obvious. In many cases the astatine tracer has not 

The low concentration of At has several consequences important in the understanding of its chemistry. 

The diatomic molecule Atj, although purported to have been identified (115), is on statistical grounds unlikely to exist, and in terms of organic syntheses there would be a negligible probability of di-astatination occurring. 

Disproportionation, a common process in inorganic halogen chemistry, does not proceed. For example, lOH(HIO) is an unstable, strongly electrophilic compound and, when no substrate is present. 

At low concentrations such a disproportionation would be virtually impossible. Therefore, when AtOH is formed it will have a relatively long lifetime. 

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An organic chemist characterizes the pure compounds she makes, often identifies samples of them with one another, and sometimes deduces their structures. These are recurring tasks that demand skill and judgment and are commonplace throughout discovery and development research. The chemists who do them work in medicinal or process chemistry, drug metabolism, radiochemistry, pharmaceutical analysis, and synthetic services. These tasks occupy much of the working life of any chemist who remains an experimentalist and reward sometimes protracted efforts to purify samples. A chemist who likes these aspects of her job, which this section introduces, enjoys her career. 

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