Q22P - Organic Chemistry (Mcmurry)

Question

Write the mechanism of the reaction shown in Figure 21-9 between coenzyme A and acetyl adenylate to give acetyl CoA.

Step-by-Step Solution

Answer

The mechanism of the reaction between coenzyme A and acetyl adenylate to give acetyl CoA can be explained.

Step 1: Diagram of the mechanism of the reaction

The mechanism can be explained as the proton abstracted by the base attached to the sulfur atom. Simultaneously, sulfur attacked the electrophilic carbon atom containing the carbonyl group. After that, it leads to the formation of an intermediate. After that, the intermediate breaks down and leads to adenosine and acetyl Co-A formation.

Mechanism

Step 2: Involvement of the reaction

The reaction mainly involves the biological nucleophilic acyl substitution. It includes two steps with one addition of nucleophile and two leaving group elimination: adenosine phosphate. The nucleophilic acyl substitution mechanism involves the biological phosphate reactions with triphosphates and acetyl-coenzyme.