My book says:
Finkelstein reaction is particularly useful for preparing iodoalkanes. The iodoalkanes are obtained by heating chloro or bromoalkanes with a concentrated solution of sodium iodide in dry acetone. $$\ce{R-X + NaI ->[\ce{acetone,~reflux}] R-I + NaX}\\ (\ce{X}=\ce{Cl,Br};\ \ce{R}=\text{alkyl group})$$ NOTE: Refluxing is a process of heating a liquid in a flask provided with a condenser. The vapours of the liquid which rise up get condensed back into the flask.
Sodium chloride and sodium bromide being less soluble in acetone get precipitated from the solution and can be removed by filtration. This also prevents the backward reaction to occur according to Le Chatelier's principle. The reaction gives the best results with primary halides.
MY QUERY
- Can we prepare alkyl chloride or alkyl bromide by Finkelstein reaction?
As we can see, first line reads that Finkelstein reaction is particularly useful for preparing iodoalkanes. The lines followed by it signify that $\ce{NaCl}$ and $\ce{NaBr}$ are less soluble in acetone. If we want to prepare alkyl chloride or alkyl bromide, we will be needed to dissolve $\ce{NaCl}$ or $\ce{NaBr}$ respectively in acetone, which is not so possible. Is it true that, we can't prepare alkyl chloride or alkyl bromide by Finkelstein reaction because of the above reasons?
