Week 9 Prac Prob Solns - Conjugation and Resonance For each of the following species if there is a conjugated-system circle all the atoms that are

Week 9 Prac Prob Solns - Conjugation and Resonance For each...

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H 2 C C CH 2 H 2 C C C H C H CH 2 H 2 C C H C H C C H C H CH 2 NH Conjugation and Resonance For each of the following species, if there is a conjugated -system, circle all the atoms that are involved in that conjugated system. (no conjugation) (no conjugation) (no conjugation) (two conjugated systems, mutually orthogonal!)
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Special Reactivity at the Allylic Position Provide complete curved-arrow mechanisms for the following reactions. Be sure to show why more than one product is observed in each case. You may ignore stereochemistry. 1. HBr (1 equiv.) 2. NaSCH 3 SCH 3 SCH 3 + Br Mg, Et 2 O (no need to show a mechanism for this step) 1. 2. H + workup O OH + HO H Br allylic resonance! :Br :Br Br Br :SCH 3 :SCH 3 MgBr allylic resonance! O O O O H H
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