Synthesis of an ester involves the reaction of alcohols with

Options

A. a ketone
B. an amide
C. `CH_(3)MgBr`
D. `RCOCl`

Explanation

To synthesize an ester, we need to understand the reaction between alcohols and certain reagents. Here’s a step-by-step breakdown of the process:

### Step 1: Identify the Reactants
The synthesis of an ester involves the reaction of an alcohol (RCH2OH) with a carbonyl compound that has a good leaving group.

### Step 2: Choose the Correct Reagent
The reagent we are looking for is a carbonyl compound (RCOX), where X is a good leaving group. Common examples of good leaving groups include halides (like Cl, Br, or I) or sulfonates.

### Step 3: Understand the Mechanism
1. The carbonyl carbon in the reagent (RCOX) is electron-deficient due to the electronegativity of the oxygen atom. This makes it susceptible to nucleophilic attack.
2. The alcohol (RCH2OH) acts as a nucleophile because the oxygen atom has a lone pair of electrons that can attack the electron-deficient carbonyl carbon.

### Step 4: Nucleophilic Attack
When the alcohol attacks the carbonyl carbon, the bond between the carbon and the leaving group (X) breaks. This results in the formation of a tetrahedral intermediate.

### Step 5: Formation of the Ester
The tetrahedral intermediate can then lose the leaving group (X) to form the ester. The final product is RCOOR', where R' is the alkyl group from the alcohol.

### Conclusion
The correct reagent for the synthesis of an ester from an alcohol is an acyl chloride (RCOCl), where Cl is a good leaving group.

### Final Answer
The synthesis of an ester involves the reaction of alcohols with acyl chlorides (RCOCl).

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