Question

Consider the above reaction and identify the missing reagent/chemical.

 

• A. DIBAL-H
• B. B₂H₆
• C. Red Phosphorus
• D. CaO

Answer 1

The Correct Option is D

To solve this problem, we need to identify the missing reagent in the given chemical reaction. The reaction involves \(\text{CH}_3\text{CH}_2\text{COO}^- \text{Na}^+\) leading to \(\text{CH}_3\text{CH}_3\), which is a decarboxylation process. 

Let’s analyze the reaction:

1. The reaction involves the removal of a carboxyl group (\(-\text{COO}^-\text{Na}^+\)) and the formation of an alkane (\(\text{CH}_3\text{CH}_3\)).
2. The transformation from a carboxylate salt to an alkane typically requires a decarboxylation process.
3. Calcium oxide (CaO) is commonly used in the soda lime method for decarboxylation reactions where a carboxylate salt is heated with solid sodium hydroxide and calcium oxide, resulting in the formation of an alkane.

Now, let’s evaluate the options:

• DIBAL-H: This is a reducing agent, commonly used for reducing esters to aldehydes and not suitable here.
• B₂H₆: This is used for hydroboration reactions and doesn't fit in the decarboxylation context.
• Red Phosphorus: Red phosphorus is used in reactions like the preparation of phosphine or reduction reactions with iodine, which is not applicable here.
• CaO: Correct choice as it is used in decarboxylation of carboxylic acids to alkanes.

Therefore, the missing reagent in the reaction is CaO, which facilitates the conversion through the decarboxylation process.

Conclusion: The correct answer is CaO.