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Nucleophilic substitution — hydroxide ions
Year 1
AQA 3.3.3
Nucleophilic substitution & elimination · NaOH or KOH (aqueous) · warm, aqueous
Watch every step, with the electron flow and reasoning shown.
Reagents: NaOH or KOH (aqueous) · Conditions: warm, aqueous
Step 1 of 1
- 1.The lone pair on the hydroxide oxygen attacks the δ+ carbon — OH⁻ is the nucleophile.
- 2.The polar C–Br bond breaks heterolytically: both electrons go to the more electronegative bromine.
OH⁻ bonds to the carbon as the C–Br bond breaks: ethanol forms and a bromide ion leaves.
Product: ethanol
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