Dehydroiodination

Dehydroiodination is a chemical reaction in which the elements of hydrogen and iodine are removed from a molecule. This typically results in the formation of a double bond or a triple bond. It is a type of elimination reaction, often occurring in organic chemistry. The process usually requires a strong base, such as potassium hydroxide or sodium ethoxide, and can be carried out in a suitable solvent. Heat is often applied to promote the reaction. Dehydroiodination is the reverse of hydroiodination, which is the addition of hydrogen iodide to an unsaturated molecule. The reaction can be used to synthesize alkenes and alkynes from alkyl halides. For example, the treatment of an alkyl dihalide with a strong base can lead to the formation of an alkyne. The regiochemistry of the elimination, meaning which hydrogen is removed, can be influenced by the base used and the reaction conditions, following rules like Zaitsev's rule or Hofmann's rule depending on the specific substrate and base. Understanding dehydroiodination is important for synthetic chemists when designing routes to specific unsaturated organic compounds.