11.5 Reaction of Acyl chlorides

In the previous section, we learned how to prepare acyl chlorides from carboxylic acids. Now, we will explore the reactions of these highly reactive compounds. Acyl chlorides are among the most reactive carboxylic acid derivatives because the chloride ion is an excellent leaving group. This section describes the key reactions of acyl chlorides with alcohols, phenol, water, ammonia, and amines.

Main Idea

The main idea is that acyl chlorides undergo nucleophilic acyl substitution reactions with a variety of nucleophiles. The general reaction is: R-COCl + Nu-H → R-CO-Nu + HCl The nucleophile (Nu-H) attacks the electrophilic carbonyl carbon, and the chloride ion is displaced as a leaving group, along with a proton. The products are carboxylic acid derivatives (esters, carboxylic acids, or amides) and hydrogen chloride gas.

Core Concept

The core concept is that the carbonyl carbon of an acyl chloride is highly electrophilic because it is bonded to two electronegative atoms (oxygen and chlorine). This makes it very susceptible to attack by nucleophiles. The chloride ion (Cl^-) is a good leaving group, which drives the reaction forward. The reaction is typically fast and exothermic, and the HCl produced is often removed by a base (like pyridine) to prevent it from protonating the nucleophile and to drive the reaction to completion.

Detailed Explanation

The textbook describes the following reactions of acyl chlorides.

1. Reaction with Alcohols (Formation of Esters)

Acyl halides react vigorously with alcohols at room temperature to produce esters. For example: CH₃COCl + CH₃CH₂OH → CH₃COOCH₂CH₃ + HCl Ethanoyl chloride + ethanol → ethyl ethanoate + hydrogen chloride.

Another example with benzoyl chloride: C₆H₅COCl + CH₃CH₂OH → C₆H₅COOCH₂CH₃ + HCl Benzoyl chloride + ethanol → ethyl benzoate + hydrogen chloride.

2. Reaction with Phenol (Formation of Esters)

Acyl chlorides react with phenol at room temperature to produce an ester. For example: CH₃COCl + C₆H₅OH → CH₃COOC₆H₅ + HCl Ethanoyl chloride + phenol → phenyl ethanoate + hydrogen chloride.

3. Reaction with Water (Hydrolysis)

Acyl halides hydrolyze with water at room temperature to produce carboxylic acids and hydrochloric acid. For example: CH₃COCl + H₂O → CH₃COOH + HCl Ethanoyl chloride + water → ethanoic acid + hydrogen chloride.

4. Reaction with Ammonia (Formation of Amides)

Acyl halides react with ammonia at room temperature to produce amides. The hydrogen chloride produced reacts with excess ammonia to give ammonium chloride. CH₃COCl + NH₃ → CH₃CONH₂ + HCl Ethanoyl chloride + ammonia → ethanamide + hydrogen chloride. HCl + NH₃ → NH₄Cl Hydrogen chloride + ammonia → ammonium chloride.

5. Reaction with Primary and Secondary Amines (Formation of N-substituted amides)

Primary and secondary amines react in a similar way as ammonia at room temperature to produce N-substituted amides. The hydrogen chloride reacts with excess amine to give an ammonium salt.

With a primary amine (methylamine): CH₃COCl + CH₃NH₂ → CH₃CONHCH₃ + HCl Ethanoyl chloride + methylamine → N-methylmethanamide + hydrogen chloride. HCl + CH₃NH₂ → [CH₃NH₃]⁺Cl^- Hydrogen chloride + methylamine → methylammonium chloride.

With a secondary amine (dimethylamine): CH₃COCl + (CH₃)₂NH → CH₃CON(CH₃)₂ + HCl Ethanoyl chloride + dimethylamine → N,N-dimethylmethanamide + hydrogen chloride. HCl + (CH₃)₂NH → [(CH₃)₂NH₂]⁺Cl^- Hydrogen chloride + dimethylamine → dimethylammonium chloride.

Intermediate Level

Acyl chlorides are highly reactive derivatives of carboxylic acids. The carbonyl carbon is very electrophilic because it is bonded to two electronegative atoms (O and Cl). This makes it susceptible to nucleophilic attack. The chloride ion is a good leaving group, so the reaction proceeds readily. The general reaction is nucleophilic acyl substitution, where a nucleophile (alcohol, water, ammonia, or amine) replaces the chloride ion. The products are esters (with alcohols or phenol), carboxylic acids (with water), or amides (with ammonia or amines). The reaction is often carried out in the presence of a base (e.g., pyridine) to neutralize the HCl produced, which would otherwise protonate the nucleophile and slow the reaction.

Important Points

• - Acyl chlorides: Highly reactive carboxylic acid derivatives.
• - General reaction: Nucleophilic acyl substitution.
• - Leaving group: Chloride ion (Cl^-).
• - Products: Esters (with alcohols/phenols), carboxylic acids (with water), amides (with ammonia/amines).
• - By-product: Hydrogen chloride (HCl).
• - Reaction with alcohols: Forms esters (e.g., ethyl ethanoate).
• - Reaction with water: Forms carboxylic acids (hydrolysis).
• - Reaction with ammonia: Forms amides (e.g., ethanamide).
• - Reaction with amines: Forms N-substituted amides.

Remember

• - Acyl chloride + alcohol → Ester + HCl.
• - Acyl chloride + phenol → Ester + HCl.
• - Acyl chloride + water → Carboxylic acid + HCl.
• - Acyl chloride + ammonia → Amide + HCl.
• - Acyl chloride + amine → N-substituted amide + HCl.
• - Chloride is a good leaving group.
• - Carbonyl carbon is electrophilic.
• - HCl is a by-product.

Common Mistakes

• - Forgetting that HCl is produced. The reaction produces hydrogen chloride gas, which can be seen as steamy fumes.
• - Thinking the reaction is slow. These reactions are fast at room temperature.
• - Confusing the product with the reactant. The product is an ester, carboxylic acid, or amide, depending on the nucleophile.
• - Not using a base to neutralize the HCl. Without a base, the HCl can protonate the nucleophile and slow the reaction.
• - Assuming that acyl chlorides are stable in water. They hydrolyze readily to carboxylic acids.

Quick Revision

Acyl chlorides are highly reactive derivatives of carboxylic acids. They undergo nucleophilic acyl substitution reactions with a variety of nucleophiles. The chloride ion is a good leaving group, and the carbonyl carbon is highly electrophilic. The reactions are fast at room temperature and produce a carboxylic acid derivative and hydrogen chloride gas. With alcohols and phenols, esters are formed; with water, carboxylic acids are formed; with ammonia, amides are formed; and with amines, N-substituted amides are formed. The reactions are often carried out in the presence of a base (e.g., pyridine) to neutralize the HCl produced.

60-Second Revision

Acyl chlorides (R-COCl) are highly reactive and undergo nucleophilic acyl substitution. They react with alcohols to form esters, with water to form carboxylic acids, with ammonia to form amides, and with amines to form N-substituted amides. In each case, hydrogen chloride (HCl) is produced as a by-product. The chloride ion is a good leaving group, and the reactions are fast at room temperature.

Frequently Asked Questions (FAQs)

• Q1. What is the general reaction of an acyl chloride with a nucleophile?
• Answer: The general reaction is nucleophilic acyl substitution:
• R-COCl + Nu-H → R-CO-Nu + HCl
• The nucleophile (Nu-H) attacks the carbonyl carbon, and the chloride ion is displaced, along with a proton, to form the product and hydrogen chloride.

• Q2. What is the product of the reaction between ethanoyl chloride and ethanol?
• Answer: The product is ethyl ethanoate (an ester) and hydrogen chloride:
• CH₃COCl + CH₃CH₂OH → CH₃COOCH₂CH₃ + HCl

• Q3. What is the product of the reaction between an acyl chloride and water?
• Answer: The product is a carboxylic acid and hydrogen chloride (hydrolysis):
• R-COCl + H₂O → R-COOH + HCl

• Q4. What is the product of the reaction between an acyl chloride and ammonia?
• Answer: The product is an amide and hydrogen chloride:
• R-COCl + NH₃ → R-CONH₂ + HCl
• The HCl reacts with excess ammonia to form ammonium chloride.

• Q5. What is the product of the reaction between an acyl chloride and a primary amine?
• Answer: The product is an N-substituted amide and hydrogen chloride:
• R-COCl + R'-NH₂ → R-CONH-R' + HCl

Q6. Why is the reaction of an acyl chloride with an alcohol fast? Answer: The reaction is fast because the carbonyl carbon of the acyl chloride is highly electrophilic (bonded to two electronegative atoms, O and Cl), and the chloride ion is a good leaving group. This makes the nucleophilic attack and subsequent elimination very favorable.

Q7. Why is a base like pyridine often added to the reaction mixture? Answer: Pyridine is added to neutralize the hydrogen chloride (HCl) produced in the reaction. If the HCl is not neutralized, it can protonate the nucleophile (e.g., the alcohol), making it less reactive, and it can also catalyze side reactions.

Q8. What is the difference between the reaction of an acyl chloride with an alcohol and with a phenol? Answer: Both reactions form esters. However, phenols are less nucleophilic than alcohols, so the reaction with phenol is slower. It may require a base catalyst (like pyridine) to proceed at a reasonable rate.

• Q9. Write the equation for the reaction of ethanoyl chloride with phenol.
• Answer:
• CH₃COCl + C₆H₅OH → CH₃COOC₆H₅ + HCl
• The product is phenyl ethanoate.

• Q10. Write the equation for the reaction of ethanoyl chloride with methylamine.
• Answer:
• CH₃COCl + CH₃NH₂ → CH₃CONHCH₃ + HCl
• The product is N-methylmethanamide.

Multiple Choice Questions (MCQs)

• Q1. What is the product of the reaction between an acyl chloride and an alcohol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q2. What is the product of the reaction between an acyl chloride and water?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: B
• Explanation: The product is a carboxylic acid.

• Q3. What is the product of the reaction between an acyl chloride and ammonia?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: C
• Explanation: The product is an amide.

• Q4. What is the by-product of the reaction of an acyl chloride with an alcohol?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride (HCl).

• Q5. Which of the following is a good leaving group in acyl chlorides?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is a good leaving group.

• Q6. What is the product of the reaction between ethanoyl chloride and ethanol?
• A. Ethyl ethanoate
• B. Methyl ethanoate
• C. Ethanoic acid
• D. Ethanamide
• Correct Answer: A
• Explanation: The product is ethyl ethanoate.

• Q7. What is the product of the reaction between ethanoyl chloride and phenol?
• A. Phenyl ethanoate
• B. Ethyl ethanoate
• C. Ethanoic acid
• D. Ethanamide
• Correct Answer: A
• Explanation: The product is phenyl ethanoate.

• Q8. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.

• Q9. What is the product of the reaction between ethanoyl chloride and ammonia?
• A. Ethanamide
• B. Ethanoic acid
• C. Ethyl ethanoate
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and methylamine?
• A. N-methylmethanamide
• B. Ethanamide
• C. Ethanoic acid
• D. Ethyl ethanoate
• Correct Answer: A
• Explanation: The product is N-methylmethanamide.

Multiple Choice Questions (MCQs)

• Q1. What is the product of the reaction between an acyl chloride and an alcohol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q2. What is the product of the reaction between an acyl chloride and water?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: B
• Explanation: The product is a carboxylic acid.

• Q3. What is the product of the reaction between an acyl chloride and ammonia?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: C
• Explanation: The product is an amide.

• Q4. What is the by-product of the reaction of an acyl chloride with an alcohol?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride.

• Q5. Which of the following is a good leaving group in acyl chlorides?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is a good leaving group.

• Q6. What is the product of the reaction between ethanoyl chloride and ethanol?
• A. Ethyl ethanoate
• B. Methyl ethanoate
• C. Ethanoic acid
• D. Ethanamide
• Correct Answer: A
• Explanation: The product is ethyl ethanoate.

• Q7. What is the product of the reaction between ethanoyl chloride and phenol?
• A. Phenyl ethanoate
• B. Ethyl ethanoate
• C. Ethanoic acid
• D. Ethanamide
• Correct Answer: A
• Explanation: The product is phenyl ethanoate.

• Q8. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.

• Q9. What is the product of the reaction between ethanoyl chloride and ammonia?
• A. Ethanamide
• B. Ethanoic acid
• C. Ethyl ethanoate
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and methylamine?
• A. N-methylmethanamide
• B. Ethanamide
• C. Ethanoic acid
• D. Ethyl ethanoate
• Correct Answer: A
• Explanation: The product is N-methylmethanamide.

Multiple Choice Questions (MCQs)

• Q1. What is the product of the reaction between an acyl chloride and an alcohol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q2. What is the product of the reaction between an acyl chloride and water?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: B
• Explanation: The product is a carboxylic acid.

• Q3. What is the product of the reaction between an acyl chloride and ammonia?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: C
• Explanation: The product is an amide.

• Q4. What is the by-product of the reaction of an acyl chloride with an alcohol?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride.

• Q5. Which of the following is a good leaving group in acyl chlorides?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is a good leaving group.

• Q6. What is the product of the reaction between ethanoyl chloride and ethanol?
• A. Ethyl ethanoate
• B. Methyl ethanoate
• C. Ethanoic acid
• D. Ethanamide
• Correct Answer: A
• Explanation: The product is ethyl ethanoate.

• Q7. What is the product of the reaction between ethanoyl chloride and phenol?
• A. Phenyl ethanoate
• B. Ethyl ethanoate
• C. Ethanoic acid
• D. Ethanamide
• Correct Answer: A
• Explanation: The product is phenyl ethanoate.

• Q8. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.

• Q9. What is the product of the reaction between ethanoyl chloride and ammonia?
• A. Ethanamide
• B. Ethanoic acid
• C. Ethyl ethanoate
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and methylamine?
• A. N-methylmethanamide
• B. Ethanamide
• C. Ethanoic acid
• D. Ethyl ethanoate
• Correct Answer: A
• Explanation: The product is N-methylmethanamide.

Multiple Choice Questions (MCQs)

• Q1. Which of the following is a reaction of acyl chlorides?
• A. With alcohols to form esters
• B. With water to form carboxylic acids
• C. With ammonia to form amides
• D. All of the above
• Correct Answer: D
• Explanation: All are reactions of acyl chlorides.

• Q2. What is the by-product of the reaction of an acyl chloride with a nucleophile?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride.

• Q3. What is the product of the reaction between an acyl chloride and a primary amine?
• A. N-substituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N-substituted amide.

• Q4. What is the product of the reaction between an acyl chloride and a secondary amine?
• A. N,N-disubstituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N,N-disubstituted amide.

• Q5. What is the product of the reaction between an acyl chloride and phenol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q6. What is the role of pyridine in the reaction of an acyl chloride with an alcohol?
• A. It acts as a nucleophile.
• B. It acts as a base to neutralize HCl.
• C. It acts as a catalyst.
• D. It acts as a solvent.
• Correct Answer: B
• Explanation: Pyridine is a base that neutralizes the HCl produced.

• Q7. What is the general name for the reaction of an acyl chloride with a nucleophile?
• A. Electrophilic addition
• B. Nucleophilic acyl substitution
• C. Electrophilic substitution
• D. Free radical substitution
• Correct Answer: B
• Explanation: The reaction is a nucleophilic acyl substitution.

• Q8. What is the leaving group in the reaction of an acyl chloride?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is the leaving group.

• Q9. What is the product of the reaction between ethanoyl chloride and dimethylamine?
• A. N,N-dimethylmethanamide
• B. N-methylmethanamide
• C. Ethanamide
• D. Ethanoic acid
• Correct Answer: A
• Explanation: The product is N,N-dimethylmethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.

Multiple Choice Questions (MCQs)

• Q1. Which of the following is a reaction of acyl chlorides?
• A. With alcohols to form esters
• B. With water to form carboxylic acids
• C. With ammonia to form amides
• D. All of the above
• Correct Answer: D
• Explanation: All are reactions of acyl chlorides.

• Q2. What is the by-product of the reaction of an acyl chloride with a nucleophile?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride.

• Q3. What is the product of the reaction between an acyl chloride and a primary amine?
• A. N-substituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N-substituted amide.

• Q4. What is the product of the reaction between an acyl chloride and a secondary amine?
• A. N,N-disubstituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N,N-disubstituted amide.

• Q5. What is the product of the reaction between an acyl chloride and phenol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q6. What is the role of pyridine in the reaction of an acyl chloride with an alcohol?
• A. It acts as a nucleophile.
• B. It acts as a base to neutralize HCl.
• C. It acts as a catalyst.
• D. It acts as a solvent.
• Correct Answer: B
• Explanation: Pyridine is a base that neutralizes the HCl produced.

• Q7. What is the general name for the reaction of an acyl chloride with a nucleophile?
• A. Electrophilic addition
• B. Nucleophilic acyl substitution
• C. Electrophilic substitution
• D. Free radical substitution
• Correct Answer: B
• Explanation: The reaction is a nucleophilic acyl substitution.

• Q8. What is the leaving group in the reaction of an acyl chloride?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is the leaving group.

• Q9. What is the product of the reaction between ethanoyl chloride and dimethylamine?
• A. N,N-dimethylmethanamide
• B. N-methylmethanamide
• C. Ethanamide
• D. Ethanoic acid
• Correct Answer: A
• Explanation: The product is N,N-dimethylmethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.

Multiple Choice Questions (MCQs)

• Q1. Which of the following is a reaction of acyl chlorides?
• A. With alcohols to form esters
• B. With water to form carboxylic acids
• C. With ammonia to form amides
• D. All of the above
• Correct Answer: D
• Explanation: All are reactions of acyl chlorides.

• Q2. What is the by-product of the reaction of an acyl chloride with a nucleophile?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride.

• Q3. What is the product of the reaction between an acyl chloride and a primary amine?
• A. N-substituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N-substituted amide.

• Q4. What is the product of the reaction between an acyl chloride and a secondary amine?
• A. N,N-disubstituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N,N-disubstituted amide.

• Q5. What is the product of the reaction between an acyl chloride and phenol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q6. What is the role of pyridine in the reaction of an acyl chloride with an alcohol?
• A. It acts as a nucleophile.
• B. It acts as a base to neutralize HCl.
• C. It acts as a catalyst.
• D. It acts as a solvent.
• Correct Answer: B
• Explanation: Pyridine is a base that neutralizes the HCl produced.

• Q7. What is the general name for the reaction of an acyl chloride with a nucleophile?
• A. Electrophilic addition
• B. Nucleophilic acyl substitution
• C. Electrophilic substitution
• D. Free radical substitution
• Correct Answer: B
• Explanation: The reaction is a nucleophilic acyl substitution.

• Q8. What is the leaving group in the reaction of an acyl chloride?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is the leaving group.

• Q9. What is the product of the reaction between ethanoyl chloride and dimethylamine?
• A. N,N-dimethylmethanamide
• B. N-methylmethanamide
• C. Ethanamide
• D. Ethanoic acid
• Correct Answer: A
• Explanation: The product is N,N-dimethylmethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.

Multiple Choice Questions (MCQs)

• Q1. Which of the following is a reaction of acyl chlorides?
• A. With alcohols to form esters
• B. With water to form carboxylic acids
• C. With ammonia to form amides
• D. All of the above
• Correct Answer: D
• Explanation: All are reactions of acyl chlorides.

• Q2. What is the by-product of the reaction of an acyl chloride with a nucleophile?
• A. Water
• B. Hydrogen chloride
• C. Carbon dioxide
• D. Hydrogen gas
• Correct Answer: B
• Explanation: The by-product is hydrogen chloride.

• Q3. What is the product of the reaction between an acyl chloride and a primary amine?
• A. N-substituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N-substituted amide.

• Q4. What is the product of the reaction between an acyl chloride and a secondary amine?
• A. N,N-disubstituted amide
• B. Ester
• C. Carboxylic acid
• D. Ketone
• Correct Answer: A
• Explanation: The product is an N,N-disubstituted amide.

• Q5. What is the product of the reaction between an acyl chloride and phenol?
• A. Ester
• B. Carboxylic acid
• C. Amide
• D. Ketone
• Correct Answer: A
• Explanation: The product is an ester.

• Q6. What is the role of pyridine in the reaction of an acyl chloride with an alcohol?
• A. It acts as a nucleophile.
• B. It acts as a base to neutralize HCl.
• C. It acts as a catalyst.
• D. It acts as a solvent.
• Correct Answer: B
• Explanation: Pyridine is a base that neutralizes the HCl produced.

• Q7. What is the general name for the reaction of an acyl chloride with a nucleophile?
• A. Electrophilic addition
• B. Nucleophilic acyl substitution
• C. Electrophilic substitution
• D. Free radical substitution
• Correct Answer: B
• Explanation: The reaction is a nucleophilic acyl substitution.

• Q8. What is the leaving group in the reaction of an acyl chloride?
• A. OH^-
• B. Cl^-
• C. NH₂^-
• D. CH₃^-
• Correct Answer: B
• Explanation: Cl^- is the leaving group.

• Q9. What is the product of the reaction between ethanoyl chloride and dimethylamine?
• A. N,N-dimethylmethanamide
• B. N-methylmethanamide
• C. Ethanamide
• D. Ethanoic acid
• Correct Answer: A
• Explanation: The product is N,N-dimethylmethanamide.

• Q10. What is the product of the reaction between ethanoyl chloride and water?
• A. Ethanoic acid
• B. Ethyl ethanoate
• C. Ethanamide
• D. Ethanol
• Correct Answer: A
• Explanation: The product is ethanoic acid.