Final answer:
But-2-enal reacts with sodium borohydride in a reduction reaction, where NaBH4 donates hydrogen to reduce the aldehyde group to an alcohol.
Step-by-step explanation:
The reaction of but-2-enal with sodium borohydride (NaBH4) is a type of reduction reaction. Sodium borohydride acts as a reducing agent, which donates hydrogen to the but-2-enal, thereby reducing the aldehyde group to an alcohol. Specifically, the carbon-oxygen double bond (carbonyl group) in the but-2-enal molecule is reduced to a carbon-oxygen single bond, converting the aldehyde into an alcohol.
The type of chemical reaction occurring when but-2-enal reacts with sodium borohydride, NaBH4, is a reduction reaction. Sodium borohydride is a strong reducing agent that can donate hydride ions (H-) to the aldehyde group in but-2-enal. This results in the conversion of the double bond in but-2-enal to a single bond and the formation of an alcohol compound.