You can't directly convert n-propylbromide (1-bromopropane) into isopropyl bromide (2-bromopropane) in a single step. This is because the reaction would involve changing the position of the bromine atom, which requires a change in the carbon skeleton.

Here's a breakdown of why and a potential multi-step solution:

Why Direct Conversion Is Difficult:

* Carbon Skeleton: The carbon skeleton of n-propylbromide is linear, while the carbon skeleton of isopropyl bromide is branched. Changing the carbon skeleton usually requires breaking and forming carbon-carbon bonds, which is not a simple process.

A Multi-Step Approach:

1. Elimination: Treat n-propylbromide with a strong base like potassium hydroxide (KOH) in alcohol. This will perform an elimination reaction, removing the bromine atom and a hydrogen from an adjacent carbon, resulting in propene (CH3CH=CH2).

2. Hydration: Treat the propene with water in the presence of an acid catalyst (like sulfuric acid). This will add a hydroxyl group (OH) to the carbon that was originally bonded to the bromine, forming isopropanol (CH3CH(OH)CH3).

3. Substitution: React isopropanol with phosphorus tribromide (PBr3). This will replace the hydroxyl group with a bromine atom, yielding isopropyl bromide (CH3CH(Br)CH3).

Overall Reaction:

n-propylbromide → propene → isopropanol → isopropyl bromide

Important Note: This is just one possible approach. Other methods might be more efficient or suitable depending on your specific requirements and available reagents.