Скачать или смотреть HX Addition to Alkenes & Alkynes | Markovnikov’s Rule, Mechanism & Rearrangements Explained

In this video, we explore the addition of hydrogen halides (HCl, HBr, HI) to carbon–carbon double and triple bonds—a classic reaction in organic chemistry that illustrates carbocation formation, regiochemistry, and rearrangements.

Topics Covered:
Mechanism for:
Alkene or alkyne donates electrons to the proton (electrophilic attack)
Formation of a carbocation intermediate
Halide ion (nucleophile) attacks the carbocation

Markovnikov’s Rule: Proton adds to the carbon with more hydrogens, halide to the one with fewer
Stereoselectivity: Overview of syn vs. anti addition
Carbocation rearrangements: Including 1,2-hydride and 1,2-methyl shifts
Extension to alkynes:
First HX addition forms an alkene
Second HX addition gives geminal or vicinal dihalides, depending on conditions

Make sure to pause at the practice problems and give them a go.

This reaction is essential for understanding how electrophiles and nucleophiles interact in alkene and alkyne chemistry, with important synthetic implications.