Question

Anti-Markownikoff addition of $HBr$ is not observed in

• A. propene
• B. butene
• C. $2$-butene
• D. $2$-pentene

Answer 1

Answer: (C)

$2$-butene

Answer 2

Anti-Markownikoff addition is not observed in $2$-butene because both the doubly bonded carbons have same number of hydrogen atoms i.e., the alkene is symmetrical.
$\underset{\text{but} -2-\text{ene}}{H_{3} C-C H=C H-C H_{3}}$