Question

Which of the above compounds will not show enolisation?

• A. $\left(A\right)$
• B. $\left(B\right)$
• C. $\left(C\right)$
• D. $\left(D\right)$

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A $\left(A\right)$
B $\left(B\right)$
C $\left(C\right)$
D $\left(D\right)$

To form enol, the carbonyl compound must contain $\alpha$ hydrogen atom.

$\alpha$ hydrogen atom is not present in the compounds of options $B$ to $D$. Hence, they will not show the enolisation.

Compound $A$ contains $\alpha$ hydrogen atom. But after enolisation, the double bond cannot attain planar geometry.

Hence, compound $A$ cannot show enolisation.