8.2 Hydrohalogenation of Alkenes | Organic Chemistry

Chad breaks down the hydrohalogenation of alkenes in which HCl, HBr, or HI is added across an alkene. Chad shows the step-by-step reaction mechanism for the addition of HBr to propene, explaining why it results in Markovnikov addition, has no stereoselectivity, and is subject to carbocation rearrangements. Chad then shows how the addition of HBr with peroxide (HBr/ROOR) proceeds through a radical mechanism resulting in anti-Markovnikov addition of HBr.

00:00 Lesson Introduction
01:08 Introduction to Hydrohalogenation
02:44 Hydrohalogenation of Alkenes Mechanism
05:09 Hydrohalogenation of Alkenes with peroxide (Addition of HBr / ROOR)

[st]

How do you know where to put the hydrogen if you have a methyl that is not on either side of the pie bond, rather its further down the chain. So it comes out to be that markovnikovs rule won't apply because when placing the hydrogen either side of the pie bond it wld have the same amount of hydrogens, but our final answer would have a difference because of the other methyl group which is already attached to the chain. Let's say if I'm adding HCl, the Cl would end up being farther or closer depending on where I place my hydrogen in step one. So which one would I choose?
Thanks, awsome vids!

[meeowdy]

Excellent video! I took organic chemistry I last semester and I felt so lost when the professor began covering more reactions, such as this. Thank you for being so clear and organized. I'm starting to feel more confident in approaching the book/homework problems!

[rachelmanavi]

chad you are amazing and a lifesaver, one thing- the sooner the better with these videos but you are great

[SeraphiraDawn]

Great videos, Professor Chad. Every semester I try to get your class & it is ALWAYS FULL 😩😩. I love the way you teach these chemistry classes, THANK YOU 😁👏🏼😁

[Josh-rmdj]

when you say that stereoselectivity is "none" around 2:09, do you mean there's no stereoselectivity just for the reaction you have shown, not that there's no stereoselectivity for all hydrohalogenation reactions? Because at the end, there is a hydrohalogenation reaction that does have chiral centers and stereoselectivity. Thanks!

[HuseyinGeyik-uveo]

Greetings from Turkey ...keep going walter white

[SeraphiraDawn]

Great videos, Professor Chad. Every semester I try to get your class & it is ALWAYS FULL 😩😩. I love the way you teach these chemistry classes, THANK YOU 😁👏🏼😁