(a)
Interpretation: Mechanism for the given type of decarboxylation reaction has to be proposed and it should be compared with the mechanism of decarboxylation of
Concept introduction:
Carboxylic acids contain a carbonyl attached to a hydroxyl group as shown below,
If
Decarboxylation of
The mechanism of thermal decarboxylation involves two processes,
- (i) Redistribution of electrons in a cyclic transition state.
- (ii) Cyclic transition state possesses keto-enol tautomerism.
(b)
Interpretation: Mechanism for the given type of decarboxylation reaction has to be proposed and it should be compared with the mechanism of decarboxylation of
Concept introduction:
Carboxylic acids contain a carbonyl attached to a hydroxyl group as shown below,
If carboxylic acid is heated to a very high temperature then of carbon dioxide will be eliminated from it this reaction is known as decarboxylation. Simple carboxylic acids do not decarboxylate readily.
Decarboxylation of
Simply the mechanism of thermal decarboxylation involves two processes,
- (i) Redistribution of electrons in a cyclic transition state.
- (ii) Cyclic transition state possesses keto-enol tautomerism.
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Chapter 17 Solutions
Organic Chemistry
- -Hydroxyketones and -hydroxyaldehydes are also oxidized by treatment with periodic acid. It is not the -hydroxyketone or aldehyde, however, that undergoes reaction with periodic acid, but the hydrate formed by addition of water to the carbonyl group of the -hydroxyketone or aldehyde. Write a mechanism for the oxidation of this -hydroxyaldehyde by HIO4.arrow_forwardFischer esterification cannot be used to prepare tert-butyl esters. Instead, carboxylic acids are treated with 2-methyIpropene in the presence of an acid catalyst to generate them. REFER IMAGE (a) Why does the Fischer esterification fail for the synthesis of tert-butyl esters?(b) Propose a mechanism for the 2-methylpropene method.arrow_forwardIn the presence of an appropriate base, esters undergo self-condensation to afford the corresponding B-ketoesters as shown below. Explain in detail using reaction schemes (not mechanisms) why route C and not routes A and B would lead to the expected product. 2 x Ethyl acetate A: NaOH(aq) B: OMe- C: OEt- EtO CH3arrow_forward
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning