Which of the following is an organometallic compound?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Methyl lithium
An organometallic compound contains a carbon–metal bond. In methyl lithium, \( \ce{CH3Li} \), the carbon of the methyl group is bonded directly to lithium, so it is organometallic, like the Grignard reagent RMgX with its C–Mg bond.
Why the other options are incorrect
Option (1) Lithium methoxide — Incorrect. In \( \ce{CH3OLi} \) lithium is bonded to oxygen (C–O–Li); there is no C–Li bond.
Option (2) Sodium acetate — Incorrect. In \( \ce{CH3COONa} \) sodium is linked to an oxygen of the carboxylate group, not to carbon.
Option (3) Lithium dimethylamide — Incorrect. In \( \ce{(CH3)2NLi} \) lithium is bonded to nitrogen; the methyl carbons are attached to N, not to the metal.
NCERT (2026-27 edition):
3. Reaction with metals – “Most organic chlorides, bromides and iodides react with certain metals to give compounds containing carbon-metal bonds. Such compounds are known as organo-metallic compounds. An important class of organo-metallic compounds discovered by Victor Grignard in 1900 is alkyl magnesium halide, RMgX, referred as Grignard Reagents.”