Allylic and Benzylic Bromination with NBS

Why is NBS preferred over Br2 for allylic and benzylic bromination?

• NBS provides a higher yield of the desired product.

• NBS is less toxic than Br2.

• NBS is cheaper than Br2.

• NBS reacts faster than Br2.

What is the main advantage of using NBS in bromination reactions?

• It is easier to handle than Br2.

• It forms more stable radicals.

• It prevents the formation of side products.

• It is more environmentally friendly.

How does NBS avoid the formation of alkene addition side products?

• By using a different solvent.

• By increasing the reaction temperature.

• By generating Br2 in low concentrations.

• By using a catalyst.

What is the significance of resonance structures in NBS bromination?

• They stabilize the reactants.

• They help predict the formation of multiple products.

• They determine the reaction rate.

• They increase the reaction temperature.

Why is it important to draw resonance structures in NBS bromination?

• To identify the solvent used.

• To calculate the reaction yield.

• To predict the formation of regioisomers.

• To determine the reaction temperature.

What is the role of light in the initiation step of NBS bromination?

• It stabilizes the radicals.

• It increases the reaction temperature.

• It breaks the nitrogen-bromine bond to form radicals.

• It acts as a catalyst.

Which step in the NBS bromination mechanism involves the formation of the desired product?

• None of the above

• Propagation

• Initiation

• Termination

What happens during the termination step of NBS bromination?

• The reaction rate increases.

• Radicals are formed.

• Radicals combine to end the reaction.

• New radicals are generated.

What is the role of HBr in the NBS bromination mechanism?

• It acts as a catalyst.

• It reacts with NBS to form Br2.

• It stabilizes the radicals.

• It increases the reaction temperature.

Which of the following is a propagation step in NBS bromination?

• Formation of radicals from NBS.

• Combination of two radicals.

• Reaction of a radical with Br2.

• Formation of HBr.