Question

What is markovnikov's rule explain with an example?

Answer 1

Markovnikov rule:

• “According to this, the addition of any group in unsymmetrical alkene, the negative part of the reagent will attach itself to the Carbon atom carrying a lesser number of Hydrogen and Hydrogen goes to the Carbon with a maximum number of hydrogen.”
• Hydrogen bromide$\left(\mathrm{HBr}\right)$ provides an electrophile, ${\mathrm{H}}^{+}$ which attacks the double bond to form carbocation as shown below:

• The primary carbocation is less stable as compared to the secondary carbocation, as per the order of stability of a carbocation which is $3^{\mathrm{o}}>2^{\mathrm{o}}>1^{\mathrm{o}}$.
• The major product thus formed in this reaction will be $2-\mathrm{Bromopropane}$: