Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Question
Chapter 22.SE, Problem 56AP
Interpretation Introduction
Interpretation:
Given that 2-substituted-2-cyclopentenones are in a base catalyzed equilibrium with their 5-substituted-2-cyclopentenone isomers. Why such analogous isomerization is not observed for 2-substituted -2-cyclohexenones is to be explained.
Concept introduction:
The isomerization of cycloalkenones occurs through an enolate anion formed by the abstraction of acidic hydrogen by the base. Hydrogens on carbon α- to a carbonyl group and those on γ- carbon in a conjugated enone are acidic. If these hydrogens are removed, isomerization will occur. Otherwise isomerization is not possible.
To explain:
Why 2-substituted -2-cyclohexenones are not in a base catalyzed equilibrium with their 6-substituted -2-cyclohexenone isomers like 2-substituted-2-cyclopentenones.
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Chapter 22 Solutions
Organic Chemistry
Ch. 22.1 - Prob. 1PCh. 22.1 - How many acidic hydrogens does each of the...Ch. 22.1 - Prob. 3PCh. 22.3 - Write the complete mechanism for the deuteration...Ch. 22.3 - Prob. 5PCh. 22.4 - If methanol rather than water is added at the end...Ch. 22.5 - Prob. 7PCh. 22.5 - Draw a resonance structure of the acetonitrile...Ch. 22.6 - If methanol rather than water is added at the end...Ch. 22.7 - Prob. 10P
Ch. 22.7 - Draw a resonance structure of the acetonitrile...Ch. 22.7 - Why do you suppose ketone halogenations in acidic...Ch. 22.7 - Prob. 13PCh. 22.7 - Prob. 14PCh. 22.7 - Prob. 15PCh. 22.7 - Prob. 16PCh. 22.SE - Prob. 17VCCh. 22.SE - Prob. 18VCCh. 22.SE - Prob. 19VCCh. 22.SE - Prob. 20MPCh. 22.SE - Predict the product(s) and provide the mechanism...Ch. 22.SE - Predict the product(s) and provide the mechanism...Ch. 22.SE - Prob. 23MPCh. 22.SE - In the Hell–Volhard–Zelinskii reaction, only a...Ch. 22.SE - Prob. 25MPCh. 22.SE - Nonconjugated , -unsaturated ketones, such as...Ch. 22.SE - Prob. 27MPCh. 22.SE - Using curved arrows, propose a mechanism for the...Ch. 22.SE - Prob. 29MPCh. 22.SE - One of the later steps in glucose biosynthesis is...Ch. 22.SE - The Favorskii reaction involves treatment of an...Ch. 22.SE - Treatment of a cyclic ketone with diazomethane is...Ch. 22.SE - Prob. 33MPCh. 22.SE - Amino acids can be prepared by reaction of alkyl...Ch. 22.SE - Amino acids can also be prepared by a two-step...Ch. 22.SE - Heating carvone with aqueous sulfuric acid...Ch. 22.SE - Identify all the acidic hydrogens (pKa 25) in the...Ch. 22.SE - Rank the following compounds in order of...Ch. 22.SE - Prob. 39APCh. 22.SE - Base treatment of the following , -unsaturated...Ch. 22.SE - Prob. 41APCh. 22.SE - Prob. 42APCh. 22.SE - Prob. 43APCh. 22.SE - Which, if any, of the following compounds can be...Ch. 22.SE - Prob. 45APCh. 22.SE - Prob. 46APCh. 22.SE - Prob. 47APCh. 22.SE - How might you convert geraniol into either ethyl...Ch. 22.SE - Prob. 49APCh. 22.SE - One way to determine the number of acidic...Ch. 22.SE - Prob. 51APCh. 22.SE - Prob. 52APCh. 22.SE - Prob. 53APCh. 22.SE - Prob. 54APCh. 22.SE - Prob. 55APCh. 22.SE - Prob. 56APCh. 22.SE - All attempts to isolate primary and secondary...Ch. 22.SE - How would you synthesize the following compounds...Ch. 22.SE - Prob. 59APCh. 22.SE - Prob. 60APCh. 22.SE - Prob. 61APCh. 22.SE - Prob. 62APCh. 22.SE - As far back as the 16th century, South American...Ch. 22.SE - The key step in a reported laboratory synthesis of...Ch. 22.SE - Prob. 65AP
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