Which of the following is a correct statement?

The correct answer is Option (3) → Biphenyls are of the poisonous nature formed by Fittig reaction

The Wurtz family of reactions couples organic halides with sodium in dry ether:

    Wurtz: \( \ce{2RX + 2Na} \xrightarrow{\text{dry ether}} \ce{R-R + 2NaX} \)

    Wurtz-Fittig: \( \ce{ArX + 2Na + RX} \xrightarrow{\text{dry ether}} \ce{Ar-R + 2NaX} \)

    Fittig: \( \ce{2C6H5Cl + 2Na} \xrightarrow{\text{dry ether}} \ce{C6H5-C6H5 + 2NaCl} \) (biphenyl)

So biphenyls are the products of the Fittig reaction, and biphenyl compounds (especially their chlorinated derivatives, the PCBs) are toxic. This is the correct statement.

Why the other options are incorrect

• Option (1) Wurtz-Fittig reaction involves acetylation and arylation — Incorrect. It joins an alkyl group and an aryl group through Na in dry ether (an alkylarene); no acetyl group (CH₃CO–) is involved.

• Option (2) Fittig reaction involves fluorine molecules — Incorrect. The reagents are an aryl halide and sodium; no \( \ce{F2} \) is used.

• Option (4) Wurtz and Fittig reactions use NaCl as reactant — Incorrect. They use sodium metal; NaCl (or NaBr) is a by-product.

Note: The question is from beyond the NCERT textbook.

NCERT (2026-27 edition):
Wurtz-Fittig Reaction