Question

Which one of the following reactions of alkenes does the Anti-Markovnikov's rule apply instead of Markovnikov's rule?

A. Hydration
B. Oxymercuration-demercuration
C. Hydroboration-oxidation
D. Addition of HCl
E. Addition of Br2

Answer 1

Anti-Markovnikov's rule applies to the Hydroboration-oxidation reaction, where the result is an alcohol with the OH group adding to the less substituted carbon of the alkene.

Step-by-step explanation:

The Anti-Markovnikov's rule applies to reactions where the addition of a proton donor and a nucleophile occurs in a manner opposite to the regioselectivity predicted by Markovnikov's rule. Among the reactions listed, Hydroboration-oxidation is the reaction where Anti-Markovnikov's rule applies. This reaction involves the addition of borane (BH3) to the less substituted carbon of the alkene, followed by oxidation, which turns the boron into a hydroxyl group. The outcome is an alcohol where the OH group adds to the carbon with the fewest hydrogen atoms. This is in contrast to Markovnikov's rule, which would suggest that the OH group should add to the more substituted carbon.