1. A methoxy group (-OMe) on an aromatic ring is electron-withdrawing when considering inductive effects, yet the methoxy group is categorized as an electron-donating group. Why? 2. A Grignard reaction needs to be run using water-exclusion techniques. Why? 3. Tertiary carbocations and radicals are more stable than primary carbocations and radicals. Why?

1. A methoxy group (-OMe) on an aromatic ring is electron-withdrawing when considering inductive effects, yet the methoxy group is categorized as an electron-donating group. Why? 2. A Grignard reaction needs to be run using water-exclusion techniques. Why? 3. Tertiary carbocations and radicals are more stable than primary carbocations and radicals. Why?

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter19: Eas: Electrophilic Aromatic Substitution

Section: Chapter Questions

Problem 17E

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Electrophilic aromatic substitutions proceed in two stages. 1. Attack of the aromatic ring on the electrophile. 2. Regeneration of the stable aromatic system by loss of a positively charged unit, usually a proton. Br Br₂/FeBr3 Draw one resonance structure for the intermediate formed when the electrophile is attacked by benzene in the reaction above. • You do not have to consider stereochemistry. • You do not have to explicitly draw H atoms. • Do not include lone pairs in your answer. They will not be considered in the grading. (+) ChemDoodleⓇ
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