Question 1

Given cyclohexene and N-bromosuccinimide (NBS) under UV light, what is the expected major product?

Accepted Answer

3-bromocyclohexene

Question 2

Which type of reaction mechanism is most likely involved when cyclohexene reacts with NBS under UV light?

Accepted Answer

Free radical substitution

Question 3

Why does NBS selectively brominate the allylic position in cyclohexene under UV light?

Accepted Answer

Because the allylic radical is stabilized by resonance

Question 4

What is the role of UV light in the reaction between cyclohexene and NBS?

Accepted Answer

It initiates the formation of bromine radicals

Question 5

Which of the following best describes the structure of the major product formed when cyclohexene reacts with NBS under UV light?

Accepted Answer

A bromine atom is attached to the carbon adjacent to the double bond

Question 6

If cyclohexene is treated with Br$$_2 in $$CCl$$_4 (no UV $$light), what is the expected major product?

Accepted Answer

Cyclohexane-1,2-dibromide

Question 7

Which of the following statements about allylic bromination is correct?

Accepted Answer

It occurs at the carbon atom adjacent to a double bond

Question 8

What is the byproduct formed when NBS is used in the bromination of cyclohexene?

Accepted Answer

Succinimide

Question 9

Which of the following best explains why NBS is preferred over Br$$_2$$ for selective allylic bromination?

Accepted Answer

NBS provides a low, steady concentration of Br$$_2$$ for radical formation

Question 10

A student attempts to brominate cyclohexene with NBS but omits the UV light. What is the most likely outcome?

Accepted Answer

Little to no reaction occurs

NBS Bromination of Cyclohexene Under UV Light

Study Guide - Practice Questions