What is the primary reaction outcome when haloalkanes react with strong bases like KOH?

When haloalkanes react with strong bases such as KOH, the primary reaction outcome is the formation of alcohols or alkenes. This reaction can proceed via two main pathways: nucleophilic substitution and elimination.

In a nucleophilic substitution reaction, the hydroxide ion (OH-) from KOH acts as a nucleophile and replaces the halogen atom in the haloalkane, resulting in the formation of an alcohol. This pathway is favored under conditions where the substrate is primary or when the reaction is performed under mild conditions.

Alternatively, in the presence of a strong base, the reaction can also undergo an elimination mechanism. This leads to the formation of alkenes through the dehydrohalogenation of the haloalkane, where the base abstracts a hydrogen atom from a carbon adjacent to the carbon holding the halide, facilitating the formation of a double bond.

The context surrounding the other options emphasizes that they are not the expected products of this reaction. The formation of esters typically occurs through the reaction of alcohols with acids or acid chlorides, not with haloalkanes and strong bases. Aldehydes usually form via oxidation reactions or reactions involving carbonyl chemistry, not through the reaction of haloalkanes with bases