Carboxylic Acids

Question 1

Name three ways to create a carboxylic acid and their limitations

Answer 1

1) KMnO4 oxidizes terminal alcohols. Cannot oxidize secondary or tertiary
2) Grignard reagents + Dry ice then acid/diethyl ether/THF. Adds an extra carbon. Useful for tertiary alkyl halides.
3) Hydrolysis of nitriles through SN2. Alkyl halide becomes alkyl nitrile, hydrolyzed (acid + H2O) to produce carboxylic acid + ammonium salt. Additional carbon added.

Question 2

How to reduce carboxylic acids?

Answer 2

LAH. NaBH4 is not powerful enough.

Question 3

How to make an ester?

Answer 3

Carboxylic acid + alcohol under acidic conditions

Question 4

How to make acyl halide from COOH?

Answer 4

Thionyl Chloride (SOCl2)

Question 5

Explain decarboxylation

Answer 5

1,3 dicarboxylic andß-keto acids spontaneously decarboxylate through 6 member ring intermediate. Give off CO2. Resulting enol tautomerizes from enol to keto.