Brominating the Allylic Position with NBS

joechem.io/videos/190 for video on jOeCHEM and attached worksheet + solution (below video on jOeCHEM aka the link).
Worksheet: worksheets.joechem.io/worksheets/benzene-subs.pdf
Worksheet Solution: worksheets.joechem.io/worksheets/benzene-subs-solution.pdf
Worksheet Solution Walkthrough: joechem.io/videos/wksht-soln-walkthrough/57
Study Guide: (To be created, but Joe's working on it!)
In this video, we discuss why the Free Radical Halogenation reaction comes up short (and doesn't work) in terms of halogenating an allylic carbon. Instead, we talk about how to leverage NBS (N-bromo succinimide) in order to brominate the allylic position, opening up a world of possibilities.
Related videos:
joechem.io/videos/15 - Free Radical Halogenation - Part 1 - The Mechanism
joechem.io/videos/61 - Halogenation of a Double Bond with Bromine and Chlorine
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[@Badgerbahalwan]

Oh dam, homie came in with the 1,2 Floyd Mayweather & the KO Anderson silva kick combo 😂

[@ahlammohammed200]

Thank you so much you're nearly the only one on KZbin who explained that reaction that well ~

[@theyoten1613]

Yours is like the only video on this reaction I could find so thank you and papa bless.

[@l7okomabenzema571]

you are amazing my teacher to explain that mechanism ;he wrote a paper and i didn't understand it but you understood it easily i hope to get a good point in organic thanks joo from morocco 🤩

[@laurenmunn5739]

This was really clear! Thanks so much!!

[@senny-]

Thank you!

[@douglasarcher58]

Love all your energy 😊! Keep up the great work 🌟

[@jOeCHEM]

Thanks, Douglas, for watching and the kind words 🤓. Make sure to check out joechem.io for FREE (yep, that's right) worksheets + solutions to go along with each video.

[@alexisjones419]

awesome video!

[@ademcavus]

Thanks a lot :)

[@reungkhongeya7244]

Love how you teach . Thank you

[@jOeCHEM]

Thank you so much, for watching and the kind words!

[@techboyzeeshan8582]

U explained really well !! But I have a question, What exactly hinders the production of bromine molecules when we use NBS?

[@jOeCHEM]

Hi tech boy Zeeshan! I'm not sure what you mean--NBS is our source of Br2, and the equilibrium established with NBS (and something like HBr) only creates a little bit of Br2. And that's a good thing, because with too much Br2, we end up doing the halogen addition across the double bond (the alkene reaction). However, with such a small source of Br2, it has a better chance to undergo homolytic cleavage and thus becoming a bromine radical.

[@Grak70]

This is actually a problem with NBS: it DOES slowly produce Br2 over time. Non-fresh NBS usually needs to be recrystallized before use for this reason.

[@Technovore88]

Thank you!