DIBAL‑H: Selective Partial Reduction (Esters/Nitriles → Aldehydes)

Learn how DIBAL‑H selectively reduces esters and nitriles to aldehydes. Mechanism, temperature control, and common workup pitfalls.

• Reaction: Ester → aldehyde (at low T); nitrile → aldehyde (with workup)
• What it does: Stops reductions early by controlled hydride delivery
• Typical reagents: DIBAL‑H, −78°C; then aqueous workup
• Key intermediate: Tetrahedral aluminum alkoxide complex
• Driving force: Controlled single hydride transfer; workup reveals aldehyde
• Exam type: Chemoselectivity
• Exam type: Reagent selection