Question

A strong base can abstract an $\alpha$-hydrogen from

• A. alkene
• B. amine
• C. ketone
• D. alkane

Answer 1

The Correct Option is C

To determine which compound a strong base can abstract an $\alpha$-hydrogen from, we need to understand the concept of $\alpha$-hydrogen.

An $\alpha$-hydrogen is a hydrogen atom that is attached to a carbon atom adjacent to a carbonyl group. These hydrogen atoms are relatively acidic because the negative charge generated after their removal (as a carbanion) can be delocalized through resonance with the carbonyl group.

Let's analyze the options:

1. Alkene: Alkenes do not have carbonyl groups, and typically do not have acidic $\alpha$-hydrogens.
2. Amine: Amines contain nitrogen atoms bonded to hydrogens and carbon chains, but do not have carbonyl groups adjacent to their hydrogens, so they also don't possess acidic $\alpha$-hydrogens.
3. Ketone: Ketones have a carbonyl group (C=O) in their structure, and thus they possess $\alpha$-hydrogens. These $\alpha$-hydrogens are slightly acidic because the carbanion formed after the removal of the hydrogen can resonate with the carbonyl group. This makes them susceptible to abstraction by a strong base.
4. Alkane: Alkanes are saturated hydrocarbons, and their carbon-hydrogen bonds are not acidic. They lack a carbonyl group that can stabilize a negative charge, meaning they do not have acidic $\alpha$-hydrogens.

Based on the analysis, the correct answer is that a strong base can abstract an $\alpha$-hydrogen from a ketone.

Thus, the correct answer is: ketone.