Question

Which one of the following is not a five-membered heterocyclic compound?
(A)Pyrrole
(B) Furan
(C) Thiophene
(D) Pyridine​

Answer 1

Answer:

thiophene (dycydudrdysyffx)

Answer 2

Option (D) Pyridine is not a five-membered heterocyclic compound.

Explanation:

(A) Pyrrole -

• It is a heterocyclic aromatic organic compound.
• It is a five-membered ring with the formula C4H4NH.
• It is a colorless volatile liquid that darkens readily upon exposure to air

(B) Furan -

• Furan is a heterocyclic organic compound
• It is consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom.
• It is a colorless, flammable, highly volatile liquid with a boiling point close to room temperature.

(C) Thiophene-

• Thiophene is a heterocyclic compound
• It has a formula $C4H4S.$
• It consist of a planar five-membered ring.
• It is a colorless liquid with a benzene-like odor.

d) Pyridine -

• It is a basic heterocyclic organic compound
• It has a chemical formula $C5H 5N.$
• It is  related structurally to benzene, with one methine group $(=CH)$ replaced by a nitrogen atom.
• It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell.