(a)
Interpretation: The species which are used for the transesterification of esters other than acids has to be identified.
Concept introduction:
Transesterification is the process of formation of a new ester molecule from the reaction of alcohol and an ester. This is like hydrolysis of ester but here nucleophile is alcohol molecule instead of
If a better nucleophile is used in place of alcohol molecule that will also increase the rate of transesterification reaction. The conjugate base of an alcohol is an alkoxide which is a better nucleophile and can attack the carbonyl carbon even its oxygen is not protonated.
(b)
Interpretation: The rate of aminolysis reaction of esters does not increase in presence of
Concept introduction: The reaction of a
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Organic Chemistry (8th Edition)
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- 22. The stability of carbocation can be accounted by which of the following structural effect? a. hyperconjugation b. inductive effect d. both a andb C. resonance 23. Secondary amines are more basic than primary amines because of what structural effect? a. hyperconjugation b. inductive effect C. resonance d. steric effectarrow_forward2. In the synthesis of peptides, carboxylic acids are condensed with amines in the present of a reagent such as dicyclohexylcarbodiimide (DCC) [Section 25.6]. a. Propose a mechanism for the following, using curved arrow notation. H₂N. glycine OH H₂N 요. glycine OH DCC H₂N. N H gly-gly LOHarrow_forwardExplain why the rate of aminolysis of an ester cannot be increased by H+, HO-, or RO-.arrow_forward
- A generic ester is shown. What happens in a transesterification reaction? R —С—0—R In a transesterification, reaction with ROH replaces the OR, group with the OR. reaction with ROH replaces the R, group with the OR. reaction with ROH replaces both the R, group and the OR, group with the OR. reaction with ROH replaces the carbonyl group with the OR,arrow_forwardDraw the organic products formed in the following reaction.arrow_forward5. Make the following via acetoacetic ester synthesis. شد کاarrow_forward
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