Organic Chemistry
8th Edition
ISBN: 9781305580350
Author: William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher: Cengage Learning
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Textbook Question
Chapter 24, Problem 24.17P
The following transformation involves a series of four consecutive Heck reactions and the formation of the four-ring steroid nucleus (Section 26.4) as a racemic mixture. Propose structural formulas for the palladium-containing intermediates involved in this reaction.
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The acetoacetic ester synthesis is a carbonyl alkylation reaction. It is used to prepare methyl ketones from primary alkyl halides, lengthening the carbon chain by three atoms. Thus, the product can be
visualized as being a "substituted acetone." The reaction consists of three steps: generation of the enolate anion followed by SN2 reaction with a primary alkyl halide, ester hydrolysis under acid
conditions, and decarboxylation.
м
Br
H3C
H3C
OEt
1. NaOEt
2. H₂O*
3. heat
H₂C.
Draw curved arrows to show the movement of electrons in this step of the mechanism.
CO₂
EtOH
CH3
Arrow-pushing Instructions
H3C
1:0:
:0:
:Br:
Br:
H₂C
CH3
CH3
H3C
CH3
7b
The acetoacetic ester synthesis is a carbonyl alkylation reaction. It is used to prepare methyl ketones from primary alkyl halides, lengthening the carbon chain by three atoms. Thus, the product can be
visualized as being a "substituted acetone." The reaction consists of three steps: generation of the enolate anion followed by SN2 reaction with a primary alkyl halide, ester hydrolysis under acid
conditions, and decarboxylation.
Br
H₂C
H3C
1. NaOEt
2. H₂O*
3. heat
H₂C.
OEt
Draw curved arrows to show the movement of electrons in this step of the mechanism.
Arrow-pushing Instructions
H
X
CO2
CH3
+
EtOH
:OH
На
CH3
CO2
CH3
CH3
CH3
Esters can be prepared by the reaction of carboxylic acids with alcohols. Bearing this in mind, propose a route to the preparation of γ-Butyrolactone, the structure of which is shown below.
Chapter 24 Solutions
Organic Chemistry
Ch. 24.3 - Prob. 24.1PCh. 24.3 - Prob. 24.2PCh. 24.4 - Prob. 24.3PCh. 24.5 - Show how the following compound can be prepared...Ch. 24.5 - Prob. 24.5PCh. 24.5 - Prob. 24.6PCh. 24.6 - Prob. 24.7PCh. 24 - Prob. 24.8PCh. 24 - Prob. 24.9PCh. 24 - Prob. 24.10P
Ch. 24 - Treatment of cyclohexene with iodobenzene under...Ch. 24 - Prob. 24.12PCh. 24 - Prob. 24.13PCh. 24 - The aryl diene undergoes sequential Heck reactions...Ch. 24 - Heck reactions take place with alkynes as well as...Ch. 24 - Prob. 24.16PCh. 24 - The following transformation involves a series of...Ch. 24 - Show the sequence of Heck reactions by which the...Ch. 24 - Prob. 24.19PCh. 24 - Write the steps that are critical in the following...Ch. 24 - Prob. 24.21PCh. 24 - Prob. 24.22PCh. 24 - Prob. 24.23PCh. 24 - Show how the following compound could be prepared...Ch. 24 - It is typically very difficult to do a...Ch. 24 - The compound eutypine is an antibacterial agent...Ch. 24 - Prob. 24.27PCh. 24 - Prob. 24.28PCh. 24 - Prob. 24.29PCh. 24 - Prob. 24.30PCh. 24 - Prob. 24.31PCh. 24 - Prob. 24.32PCh. 24 - Prob. 24.33PCh. 24 - The following transformation can be accomplished...Ch. 24 - Prob. 24.35PCh. 24 - Prob. 24.36PCh. 24 - Prob. 24.37PCh. 24 - Prob. 24.38PCh. 24 - E. J. Coreys 1964 total synthesis of...Ch. 24 - Prob. 24.40P
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