MHT CET 202625 AprilEvening Shift
- Exam
- MHT CET
- Year
- 2026
- Date
- 25 April
- Shift
- Evening Shift
- Subject
- Chemistry
- Chapter
- Hydrocarbons
MHT CET 2026 · 25 April · Evening Shift · Chemistry · Hydrocarbons
H_3C-CH=CH_2 + H-Br (C_6H_5CO)_2O_2,\ Benzoyl peroxide...
Which of the following rules is followed when the above reaction occurs?
Options
- AMarkovnikovs rule
- BAnti-Markovnikovs rule
- CSaytzeff rule
- DHuckel rule
Correct answer
B. Anti-Markovnikovs rule
Step-by-step solution
The addition of to an unsymmetrical alkene in the presence of a peroxide (such as benzoyl peroxide) proceeds via a free radical mechanism.
The bromine free radical adds to the less substituted carbon atom of the double bond to generate a more stable secondary free radical intermediate.
This leads to the formation of 1-bromopropane () as the major product.
This regioselectivity is opposite to Markovnikov's rule and is known as the peroxide effect, Kharasch effect, or Anti-Markovnikov's rule.
Answer: Anti-Markovnikovs rule
The bromine free radical adds to the less substituted carbon atom of the double bond to generate a more stable secondary free radical intermediate.
This leads to the formation of 1-bromopropane () as the major product.
This regioselectivity is opposite to Markovnikov's rule and is known as the peroxide effect, Kharasch effect, or Anti-Markovnikov's rule.
Answer: Anti-Markovnikovs rule