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Electrophilic addition — concentrated H2SO4
Year 1
AQA 3.3.4
Electrophilic addition · concentrated H2SO4 · cold
Reagents: concentrated H2SO4 · Conditions: cold
Step 1 of 2
- 1.The π electrons attack the δ+ hydrogen of the O–H bond.
- 2.The O–H bond breaks heterolytically towards oxygen, releasing the hydrogensulfate ion.
A carbocation and a hydrogensulfate ion form.
Step 2 of 2
- 1.A lone pair on the hydrogensulfate oxygen bonds to the positive carbon.
Ethyl hydrogensulfate forms.
Product: ethyl hydrogensulfate
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