18.6 Malonic ester synthesis
The following dicarboxylic acid is called malonic acid. The ester it makes is called malonic ester.
In the malonic ester synthesis, malonic ester is first deprotonated between the carbonyl groups. The resulting enolate reacts with an alkyl halide via an SN2 reaction to alkylate it. Once the ester is hydrolyzed with acid and heat, the esters turn into a carboxylic acid.
It decarboxylates to form a substituted acetic acid because the carboxylic acid is beta to another carbonyl group.
Take a moment and cover up the red square directly above with your thumb. When you cover up the CO2 of the carboxylic acid (in the red square) with your thumb, you get the product on the right. Covering the carboxylic acid with your thumb is a quick way to envision the product you get following decarboxylation.
9. Draw the products of the following reactions.
9. Draw the products of the following reactions.
10. Circle all of the molecules in the following group that can decarboxylate.
10. Circle all of the molecules in the following group that can decarboxylate.
