Question

Which of the following halogen exchange reaction will occur in dry acetone?

• A. $R-I+NaCl\to$
• B. $R-Cl+NaBr\to$
• C. $R-Cl+NaI\to$
• D. $R-F+AgBr\to$

Answer 1

The correct option is C $R-Cl+NaI\to$

Bromides and chlorides are insoluble in acetone and hence they can't form a solution with acetone to react with alkyl halides. Sodium iodide, however, is soluble in acetone thus forms a solution with acetone and reacts with alkyl halides, thus undergoing Finkelstein reaction to form corresponding alkyl iodide.
The general reaction is shown below:
Hence, the correct option is 'c'.
$\underset{\text{Ethyl Chloride}}{C_2{H}_{5}Cl}+NaI\underset{\text{Heat}}{\overset{\text{Dry Acetone}}{\to }}\underset{\text{Ethyl Iodide}}{C_2{H}_{5}I}+NaCl\downarrow$