The compound shown is treated with DIBAL-H (1 equivalent) in toluene at -78 degC, and then quenched with H3O+. Which structure is the main product?

MolSynapse / Question bank / Reduction, Oxidation and Hydrolysis in Organic Chemistry / Hydride reductions of drawn compounds (LiAlH4 / NaBH4 / DIBAL-H)

JEE Main levelSingle correct optionDifficulty 2 of 3ro234

The compound shown is treated with $DIBAL - H$ (1 equivalent) in toluene at $- 7 8^{\circ} C$ , and then quenched with $H X_{3} O X^{+}$ . Which structure is the main product?

AStructure A
BStructure B
CStructure C
DStructure D

Answer: C

The compound is methyl cyclohexanecarboxylate. At

- 7 8^{\circ} C

with one equivalent, DIBAL-H adds a single hydride and the tetrahedral aluminium hemiacetal is stable until work-up, which releases cyclohexanecarbaldehyde.

LiAlH X_{4}

would give the primary alcohol, and no acid or methyl compound is formed.

Practice Reduction, Oxidation and Hydrolysis in Organic Chemistry More on Hydride reductions of drawn compounds (LiAlH4 / NaBH4 / DIBAL-H)

Previous questionNext question

The compound shown is treated with DIBAL−H (1 equivalent) in toluene at −78∘C, and then quenched with HX3​OX+. Which structure is the main product?

Answer: C

More questions on Hydride reductions of drawn compounds (LiAlH4 / NaBH4 / DIBAL-H)

The compound shown is treated with $DIBAL - H$ (1 equivalent) in toluene at $- 7 8^{\circ} C$ , and then quenched with $H X_{3} O X^{+}$ . Which structure is the main product?