Fundamentals of Organic Chemistry
- Exam
- Fundamentals of Organic Chemistry
- Subject
- Chemistry
- Chapter
- Carboxylic Acid Derivatives
Fundamentals of Organic Chemistry · Chemistry · Carboxylic Acid Derivatives
Three of the four reactions shown below proceed as shown to give...
Three of the four reactions shown below proceed as shown to give good yields. Identify the one reaction that will not proceed as indicated.
Options
- A
- B
- C
- D
Correct answer
C.
Step-by-step solution
The relative reactivity of carboxylic acid derivatives towards nucleophilic acyl substitution follows the order: Acyl chlorides > Acid anhydrides > Esters > Amides > Carboxylate ions.
A more reactive derivative can be converted into a less reactive derivative, but the reverse reaction is generally not possible without special reagents.
Option (A): Ethyl acetate (an ester) reacts with ethylamine to form N-ethylacetamide (an amide). Since esters are more reactive than amides, this aminolysis reaction proceeds in good yield.
Option (B): Acetyl chloride reacts with acetate ion to form acetic anhydride. Since acyl chlorides are more reactive than acid anhydrides, this reaction proceeds readily.
Option (C): N-ethylacetamide (an amide) is reacted with ethanol to form acetic anhydride (or an ester). Amides are the least reactive among these derivatives and cannot be directly converted into an ester or an anhydride by simply reacting with an alcohol. Thus, this reaction will not proceed as indicated.
Option (D): Acetyl chloride reacts with ethanol to form ethyl acetate (an ester). Since acyl chlorides are more reactive than esters, this alcoholysis reaction proceeds easily.
A more reactive derivative can be converted into a less reactive derivative, but the reverse reaction is generally not possible without special reagents.
Option (A): Ethyl acetate (an ester) reacts with ethylamine to form N-ethylacetamide (an amide). Since esters are more reactive than amides, this aminolysis reaction proceeds in good yield.
Option (B): Acetyl chloride reacts with acetate ion to form acetic anhydride. Since acyl chlorides are more reactive than acid anhydrides, this reaction proceeds readily.
Option (C): N-ethylacetamide (an amide) is reacted with ethanol to form acetic anhydride (or an ester). Amides are the least reactive among these derivatives and cannot be directly converted into an ester or an anhydride by simply reacting with an alcohol. Thus, this reaction will not proceed as indicated.
Option (D): Acetyl chloride reacts with ethanol to form ethyl acetate (an ester). Since acyl chlorides are more reactive than esters, this alcoholysis reaction proceeds easily.