Nucleophilic addition — NaBH₄ (reduction to alcohols)
Carbonyl & aromatic chemistry · NaBH₄ in water/methanol · room temperature
Watch every step, with the electron flow and reasoning shown.
Reagents: NaBH₄ in water/methanol · Conditions: room temperature
Step 1 of 2
- 1.The lone pair on :H⁻ attacks the δ+ carbonyl carbon, forming a new C–H bond. The arrow starts on the hydride, not on Na or B.
- 2.The C=O π bond breaks; both electrons move onto oxygen, giving an alkoxide.
Hydride adds to the carbonyl carbon and the π electrons move to O, giving an alkoxide.
Step 2 of 2
- 1.A lone pair on the alkoxide O⁻ takes a proton from water, forming the –OH group of the alcohol.
The alkoxide is protonated: propan-2-ol.
Product: propan-2-ol
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