Question

Which from following statements is true for tetrahydrofuran?

• A. It is homocyclic aromatic.
• B. It is heterocyclic aromatic.
• C. It is aromatic non-benzenoid.
• D. It is heterocyclic nonaromatic.

Hint:

Furan (with two double bonds) is heterocyclic aromatic, but tetrahydrofuran (fully saturated, no double bonds) is heterocyclic nonaromatic!

Answer 1

The Correct Option is D

Step 1: Look at the ring of THF.
Tetrahydrofuran is a five membered ring made of four carbons and one oxygen.

Step 2: Classify the ring.
An oxygen sits inside the ring, so it is heterocyclic, not all carbon.

Step 3: Check for aromaticity.
The word tetrahydro tells us the ring is fully saturated. All carbons are $sp^3$, so there is no ring of overlapping p orbitals and no aromatic character.
So THF is heterocyclic and nonaromatic.
\[ \boxed{\text{Heterocyclic nonaromatic}} \]