Do the following conversions: (i) Methyl bromide to acetone. (ii) Benzyl chloride to 2-phenyl acetic acid.

To convert methyl bromide to acetone and benzyl chloride to 2-phenyl acetic acid, we need to understand the chemical reactions involved in each transformation. Let's break down each conversion step by step.

Conversion of Methyl Bromide to Acetone

Methyl bromide (CH₃Br) can be transformed into acetone (CH₃COCH₃) through a series of reactions. The key steps involve nucleophilic substitution and oxidation processes.

Step 1: Nucleophilic Substitution

The first step involves the reaction of methyl bromide with a strong nucleophile, such as sodium hydroxide (NaOH) or potassium cyanide (KCN). This reaction can be represented as follows:

• CH₃Br + OH^- → CH₃OH + Br^-

In this reaction, the bromine atom is replaced by a hydroxyl group, forming methanol (CH₃OH).

Step 2: Oxidation to Acetone

Next, we need to convert methanol to acetone. This can be achieved through oxidation. Methanol can be oxidized to formaldehyde (CH₂O) and then further oxidized to acetone. The oxidation can be performed using an oxidizing agent like chromic acid (H₂CrO₄) or potassium dichromate (K₂Cr₂O₇).

• CH₃OH → CH₂O → CH₃COCH₃

In summary, the overall conversion from methyl bromide to acetone can be outlined as:

• CH₃Br → CH₃OH → CH₃COCH₃

Transformation of Benzyl Chloride to 2-Phenyl Acetic Acid

Benzyl chloride (C₆H₅CH₂Cl) can be converted to 2-phenyl acetic acid (C₆H₅CH(CH₂COOH)) through a nucleophilic substitution followed by a carboxylation reaction.

Step 1: Nucleophilic Substitution

The first step involves the reaction of benzyl chloride with a strong nucleophile, such as sodium cyanide (NaCN). This will replace the chlorine atom with a cyanide group:

• C₆H₅CH₂Cl + NaCN → C₆H₅CH₂CN + NaCl

This reaction yields benzyl cyanide (C₆H₅CH₂CN).

Step 2: Hydrolysis to Carboxylic Acid

The next step involves hydrolyzing benzyl cyanide to form 2-phenyl acetic acid. This can be achieved by treating benzyl cyanide with water in the presence of an acid or base:

• C₆H₅CH₂CN + H₂O → C₆H₅CH(CH₂COOH)

In this reaction, the cyanide group is converted into a carboxylic acid group, resulting in 2-phenyl acetic acid.

Summary of the Conversion

The overall transformation from benzyl chloride to 2-phenyl acetic acid can be summarized as:

• C₆H₅CH₂Cl → C₆H₅CH₂CN → C₆H₅CH(CH₂COOH)

In conclusion, both conversions involve nucleophilic substitution reactions followed by further transformations to achieve the desired products. Understanding these steps is crucial for mastering organic synthesis techniques.