Alkyl iodides can be synthesized through nucleophilic displacement of the corresponding bromide using a solution of sodium iodide in acetone. The reaction proceeds through an SN2 mechanism, and the unfavorable equilibrium position of halide exchange is shifted towards the formation of the iodide by precipitating sparingly soluble sodium bromide. This reaction is commonly known as the Finkelstein reaction and is equally effective for preparing iodides from chlorides. However, due to the SN2 mechanism, the process is more efficient with primary halides than with secondary or tertiary halides.
It is crucial to exercise caution to avoid skin contact or inhalation of alkyl halides, especially iodides, as they are highly toxic and have been implicated as potential cancer-inducing agents. Proper safety measures should always be taken to minimize any potential health risks associated with handling these substances.