1. Show the method to carry out each transformation: two-step method using a Grignard reagent. CH3 oi-or H CH3 2. Identify the reagents necessary to produce the following products of crossed aldol addition reaction: os H₂C OH 3. Propose an efficient synthesis for the following transformation: 'N CI

1. Show the method to carry out each transformation: two-step method using a Grignard reagent. CH3 oi-or H CH3 2. Identify the reagents necessary to produce the following products of crossed aldol addition reaction: os H₂C OH 3. Propose an efficient synthesis for the following transformation: 'N CI

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter24: Catalytic Carbon-carbon Bond Formation

Section: Chapter Questions

Problem 24.9P

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I H H3C NOC XT :0: MET H₂C base H3C The aldol reaction is a carbonyl condensation reaction between two carbonyl partners and involves a combination of nucleophilic addition and a-substitution steps. One partner is converted into an enolate ion nucleophile and adds to the electrophilic carbonyl group of the second partner. In the classic aldol reaction, the carbonyl partners are aldehydes or ketones, although aldehydes are more reactive. The product is a ß-hydroxy carbonyl compound. H OH q H3C H₂C H Under reaction conditions slightly more vigorous than those employed for the aldol reaction, the ß-hydroxyl group is eliminated in an E1cB dehydration to give an a,ß-unsaturated carbonyl compound. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions heat H H + H₂O
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