JEE MainChemistryAlcohols Phenols and Ethers
Consider the following reaction sequence starting with 2,2,6-trimethylcyclohexan-1-ol: 2,2,6-trimethylcyclohexan-1-ol [ ] conc. H ₂ SO ₄ B (Major Product) B [ Zn/H ₂ O ] O ₃ C C [ then H ₃ O ^+] excess I ₂ / NaOH D What is the IUPAC name of the final product D?
Options
- A2,2-dimethylhexanedioic acid
- B2,3-dimethylhexanedioic acid
- C3-methyloctane-2,7-dione
- D2-methylhexanedioic acid
Correct answer
D. 2-methylhexanedioic acid
Step-by-step solution
Dehydration of 2,2,6-trimethylcyclohexan-1-ol with concentrated H ₂ SO ₄ generates a secondary carbocation at C-1. To relieve the steric strain of the gem-dimethyl group and form a more stable product, a 1,2-methyl shift occurs from C-2 to C-1, rather than a hydride shift from C-6. Elimination of a proton yields the most stable tetrasubstituted alkene, 1,2,3-trimethylcyclohexene (Product B). Reductive ozonolysis ( O ₃ , Zn/H ₂ O ) of 1,2,3-trimethylcyclohexene cleaves the double bond to form a diketone. The ring op