Question

What is the structure of Tetrahydrofuran (THF)?

• A. 5-membered saturated ring with 1 oxygen and 4 carbon atoms
• B. 4-membered ring with 1 oxygen and 3 carbon atoms
• C. 6-membered ring with 2 oxygen atoms
• D. Benzene ring containing oxygen

Hint:

Remember the important oxygen-containing heterocyclic compounds: \[ \boxed{ \begin{aligned} \text{Oxirane} &\rightarrow 3\text{-membered ring}\\ \text{Oxetane} &\rightarrow 4\text{-membered ring}\\ \text{THF} &\rightarrow 5\text{-membered saturated ring}\\ \text{Furan} &\rightarrow 5\text{-membered aromatic ring} \end{aligned} } \] THF is one of the most commonly used polar aprotic solvents.

Answer 1

The Correct Option is A

Concept: Tetrahydrofuran (THF) is a saturated cyclic ether obtained by the hydrogenation of furan. Its molecular formula is \[ \boxed{C_4H_8O.} \] THF consists of

• One oxygen atom.

• Four carbon atoms.

• A five-membered saturated ring.
It is widely used as a polar aprotic solvent in organic chemistry.

Step 1: Understand the structure of THF.
The ring contains \[ 4 \text{ carbon atoms } + 1 \text{ oxygen atom}. \] Hence, the total number of atoms in the ring is \[ \boxed{5.} \]

Step 2: Determine whether the ring is saturated or unsaturated.
Unlike furan, THF contains only single bonds. Therefore, \[ \boxed{\text{THF is a saturated cyclic ether}.} \]

Step 3: Compare with the given options.

• Option (A): Correct description of THF.

• Option (B): Represents oxetane (4-membered ring).

• Option (C): Represents a six-membered oxygen-containing ring.

• Option (D): Incorrect because THF is non-aromatic.
Hence, \[ \boxed{\textbf{Option (A)}} \] is the correct answer.