Question

What does reacting Grignard reagents w/ CO₂ form?

Answer 1

Reacting Grignard reagents with CO₂ forms carboxylic acids through a step-by-step process: the Grignard reagent attacks the carbon atom of CO₂, forming a metal carbonate intermediate, which is then protonated to yield a carboxylic acid.

Step-by-step explanation:

When Grignard reagents react with carbon dioxide (CO₂), they form carboxylic acids. The reaction involves the addition of the Grignard reagent to the carbon atom of CO₂, followed by protonation to form the carboxylic acid. Here is the step-by-step reaction:

1. The Grignard reagent, R-MgX, where R is an organic group and X is a halogen, reacts with CO₂.
2. The nucleophilic carbon atom of the Grignard reagent attacks the electrophilic carbon atom of the CO₂ molecule, forming a metal carbonate intermediate.
3. The metal carbonate intermediate is then protonated by water or an acid, resulting in the formation of a carboxylic acid, R-COOH.

For example, if the Grignard reagent is phenylmagnesium bromide (PhMgBr), it will react with CO₂ to form benzoic acid (C₆H₅COOH).