Why does 1-chlorobutane give a precipitate while I-iodopropane does not when reacted with sodium iodide in acetone even though both are primarily alkyl halide?

Answer 1

1-Chlorobutane gives a precipitate when reacted with sodium iodide in acetone because it undergoes an SN2 reaction, where the iodide ion displaces the chloride ion, forming a less soluble product that precipitates out of the solution. In contrast, i-iodopropane does not precipitate because it is a tertiary alkyl halide, which typically undergoes an SN1 mechanism; this reaction does not produce a solid precipitate. The difference in reactivity and solubility of the resulting products accounts for the observed precipitate formation.