Identify D in this reaction:

The correct answer is option 3.

The reaction sequence outlines the transformation of 3-bromobenzoic acid into 3-bromobenzamine. Here is a detailed explanation of each step in the sequence:

Conversion of 3-Bromobenzoic Acid to 3-Bromobenzoyl Chloride:

The carboxylic acid group of 3-bromobenzoic acid is converted to an acyl chloride using thionyl chloride (\(\text{SOCl}_2\)). This reaction replaces the hydroxyl group with a chloride group.

Conversion of 3-Bromobenzoyl Chloride to 3-Bromobenzamide:

The acyl chloride (3-bromobenzoyl chloride) reacts with ammonia (\(\text{NH}_3\)) to form the corresponding amide (3-bromobenzamide). Ammonia acts as a nucleophile and attacks the carbonyl carbon, displacing the chloride ion.

Conversion of 3-Bromobenzamide to 3-Bromobenzamine:

This step involves the Hofmann degradation of 3-bromobenzamide using sodium hydroxide (\(\text{NaOH}\)) and bromine (\(\text{Br}_2\)). In this reaction, the amide is converted to a primary amine (3-bromobenzamine) by the loss of one carbon atom. This reaction is a common method for reducing amides to amines.

So, the complete sequence of transformations is: