Chapters 20 and 21: Carboxylic Acids and their Derivatives

Question 1

In the synthesis of an acid chloride using SOCl2, what can the R group on the carboxylic acid reagent never contain? Why?

Answer 1

One or more alkenes; because the reaction conditions are harsh with the generation of HCl (the alkene will react).

Question 2

What is the acidity of a carboxylic acid due to?

Answer 2

The resonance stabilization of the conjugate base.

Question 3

How could you make benzoic acid in a solution of CH2Cl2 water soluble?

Answer 3

Deprotonate the benzoic acid using a base whose conjugate acid is greater than that of benzoic acid.

Question 4

What intermediate must you have in an oxidation reaction of an alcohol to get to the carboxylic acid?

Answer 4

A hydrate intermediate

Question 5

What are the three major parts of addition/elimination reaction mechanisms for carboxylic acids?

Answer 5

1) Turn the OH into a good LG.
2) Addn of the nucleophile to the carbonyl carbon and formation of tetrahedral intermediate.
3) Eliminate the LG and reform the carbonyl.

Question 6

By what mechanism are carboxylic acid derivatives formed?

Answer 6

Addition/Elimination

Question 7

What are the carboxylic acid derivatives?

Answer 7

1) Acid Halides
2) Anhydrides
3) Esters
4) Amides
5) Nitriles

Question 8

What can carboxylic acid derivatives be hydrolyzed to yield?

Answer 8

A carboxylic acid

Question 9

How can you get a carboxylic acid from a carboxylic acid derivative?

Answer 9

Hydrolysis

Question 10

Under what conditions is hydrolysis from a carboxylic acid to a derivative usually done?

Answer 10

Acidic

Question 11

Under what conditions is hydrolysis from a derivative to a carboxylic acid usually done? What is the exception?

Answer 11

Basic; amides are the exception

Question 12

What type of mechanism is a hydrolysis reaction?

Answer 12

Addition/elimination