Hydrohalogenation - Alkene Reaction Mechanism

Are you struggling with organic chemistry? Download my free ebook "10 Secrets To Acing Organic Chemistry" here: leah4sci.com/orgo-ebook/
leah4sci.com/organicchemistry/ presents: Alkene Reaction Mechanisms HYDROHALOGENATION, or the reaction of adding H-X to an alkene
This is the second video in my Alkene Reaction Mechanism series taking you step by step through the most common alkene reaction mechanisms focusing on the why and how in place of memorization
For questions and comments, find me on social media here:
Facebook: / leah4sci
Twitter: / leah4sci
Instagram: / leah4sci
Pinterest: / leah4sci
I would also love for your to join my weekly live online organic chemistry review session
leah4sci.com/organic-chemistry...

Пікірлер: 110

  • @gravityclarity
    @gravityclarity9 жыл бұрын

    There are so many reaction mechanisms that I don't really remember the ones I learned when I took orgo. This is nice review.

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    So glad this helped!

  • @jeremybranson6157
    @jeremybranson61578 жыл бұрын

    May life be long and prosperous, Leah!

  • @Leah4sci

    @Leah4sci

    6 ай бұрын

    thank you!

  • @alex_PR15
    @alex_PR158 жыл бұрын

    Great explanation!! I sometimes struggle to understand who attacks who, but now looking at it this way I can picture it much easier than I expected. Thank you for this explanation!!

  • @Leah4sci

    @Leah4sci

    6 ай бұрын

    You're so welcome, I'm happy to share!

  • @ratpoizon
    @ratpoizon8 жыл бұрын

    I can just listen to your clear ochem gospel all day long

  • @Leah4sci

    @Leah4sci

    6 ай бұрын

    Why thank you very much!

  • @michaelpa1110
    @michaelpa11105 жыл бұрын

    Thank you so much for the clarity of your videos!!

  • @Leah4sci

    @Leah4sci

    5 жыл бұрын

    You are very much welcome. Don't forget to subscribe! :)

  • @sar0235
    @sar023510 жыл бұрын

    my professor has podcasts that were required to watch and their terrible! These videos are awesome. Thank you! I'm sure you have heard this before, but your a life saver.

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    Ugh, sorry about the terrible podcasts but glad I could help!

  • @red-baitingswine8816
    @red-baitingswine8816 Жыл бұрын

    I like your use of Markovnikov's idea here! It both plausibly explains these reactions and teaches us Markovnikov's rule. Both easier to use and more educational about Chem generally.

  • @Leah4sci

    @Leah4sci

    Жыл бұрын

    thank you :)

  • @nkosinathinkosi9807
    @nkosinathinkosi9807 Жыл бұрын

    omg you are a star! watchingg the entire series

  • @Leah4sci

    @Leah4sci

    Жыл бұрын

    So glad you're liking the videos! Thanks :)

  • @amberchen2416
    @amberchen24167 жыл бұрын

    thank you so much i was so lost before you don't understand how grateful i am

  • @Leah4sci

    @Leah4sci

    7 ай бұрын

    You're very welcome, so glad it helped!

  • @Transformer2012r
    @Transformer2012r9 жыл бұрын

    thanks a lot!!! you made my life so much easier :D keep making more videos :D You're awesome!

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    You're so very welcome!

  • @tonkymolly
    @tonkymolly7 жыл бұрын

    Finally makes sense. Thank you so much!

  • @Leah4sci

    @Leah4sci

    6 ай бұрын

    You're so welcome, happy to help clear it up!

  • @sarahholland5980
    @sarahholland59803 жыл бұрын

    the carbocation argument is so much easier for me to understand/remember. thank you!

  • @Leah4sci

    @Leah4sci

    3 жыл бұрын

    You're welcome!

  • @rashally
    @rashally9 жыл бұрын

    Thanks a lot, this have been really helpful. I am now able to remember each because they are so similar.

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    You're welcome, happy to help!

  • @eman4159
    @eman41594 ай бұрын

    The best of the bestsssss💗💗💗💗💗 thank youuuuu thank youuuuu

  • @Leah4sci

    @Leah4sci

    4 ай бұрын

    You're very welcome

  • @taushabrazier1
    @taushabrazier110 жыл бұрын

    You are so great!! Thank you!

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    You're welcome!

  • @9604993605
    @96049936058 жыл бұрын

    I become fan of your lecture mam....really helpful..the stereo-chemistry portion is really lucid and easy to memorize....Thanks a lot you..

  • @Leah4sci

    @Leah4sci

    6 ай бұрын

    You're very welcome, happy to help!

  • @brianm.4368
    @brianm.43687 жыл бұрын

    I'm currently a paying subscriber and her other paid videos make learning this way way better. These videos compliment them well but her other videos bring an added element to the learning experience.

  • @Leah4sci

    @Leah4sci

    7 жыл бұрын

    Thank you for your kind words. I'm glad you are finding them helpful :)

  • @cmhardin37

    @cmhardin37

    6 жыл бұрын

    What other paid videos?

  • @MrYaseen100

    @MrYaseen100

    6 жыл бұрын

    Brian M. How much is it?

  • @1BigMan.Tshepo
    @1BigMan.Tshepo Жыл бұрын

    this video saved my life omg.

  • @Leah4sci

    @Leah4sci

    Жыл бұрын

    Wow, you give it too much credit! Always glad to help. :)

  • @mukulsharma5738
    @mukulsharma57389 жыл бұрын

    you are just making my organic chemistry easy to understand :) thanx

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    So happy to help!!!

  • @mukulsharma5738

    @mukulsharma5738

    5 ай бұрын

    @@Leah4sci Did you just reply to my comment after 9 years ?? wow hahah ....That's actually amazing 😂

  • @tilahungetnet7698
    @tilahungetnet76983 жыл бұрын

    Thanks ,you are my hero!

  • @Leah4sci

    @Leah4sci

    3 жыл бұрын

    Awww, you're so welcome!

  • @kaelaboulay9319
    @kaelaboulay93193 жыл бұрын

    thank you! this was very easy to understand.

  • @Leah4sci

    @Leah4sci

    3 жыл бұрын

    You're very welcome!

  • @mindyschaper
    @mindyschaper11 жыл бұрын

    Lovely as usual.

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    Thank you!

  • @hyderusmael7343
    @hyderusmael73439 жыл бұрын

    thank you very much Leah you made it simple

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    You're so welcome, happy to help!

  • @amalmqb
    @amalmqb9 жыл бұрын

    amazing!!

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    thanks!

  • @TheNabilah95
    @TheNabilah9510 жыл бұрын

    thanks a lot..it's really help..

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    You're very welcome, happy to help

  • @mutintachibala7097
    @mutintachibala70974 жыл бұрын

    Hey I love your work here but just an addition to this concept could you also show what products we would expect to get when we repeat the last reaction but with a hydride shift to it?

  • @Leah4sci

    @Leah4sci

    7 ай бұрын

    I just posted a new video on the hydrate shift reaction mechanism. I hope it helps

  • @zaidkilane1974
    @zaidkilane19742 жыл бұрын

    thank you very much

  • @Leah4sci

    @Leah4sci

    2 жыл бұрын

    You're so welcome!

  • @ginsy1
    @ginsy111 жыл бұрын

    Question. Would the attack from the halogen be considered a back side attack? meaning it would be facing the opposite direction from the hydrogen? (if forced to draw a dash-wedged diagram)

  • @Brucelee135974
    @Brucelee13597411 жыл бұрын

    I love you. I truly love you.

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    thanks!

  • @ahmedarif1457
    @ahmedarif1457 Жыл бұрын

    Very great

  • @Leah4sci

    @Leah4sci

    Жыл бұрын

    Glad you like it, thanks for watching!

  • @KoolViking3
    @KoolViking310 жыл бұрын

    Does the Hydrogen (7:52) go to the primary CH2? Thanks! Loving your videos!

  • @JayTee11
    @JayTee118 жыл бұрын

    Thank you.

  • @Leah4sci

    @Leah4sci

    6 ай бұрын

    you are very welcome

  • @scottseptember1992
    @scottseptember199211 жыл бұрын

    It would be a good idea to also mention the idea of "hydride shifting" in this matter. At 6:55 even if someone drew the first intermediate with a secondary carbocation, one should always look if a shift of some type (hydride or alkyl) can occur that leads from a less stable carbocation to a more stable carbocation. The newly formed bond with the tertiary hydrogen can shift to the secondary carbocation, and leave a tertiary carbocation where the hydrogen previously was.

  • @Leah4sci

    @Leah4sci

    Ай бұрын

    I didn't think of it when I recorded this video, but I have since recorded a more updated one showing the carbocation rearrangement via hydride shift

  • @scottseptember1992

    @scottseptember1992

    Ай бұрын

    @@Leah4sci Hey! Thanks for replying! Nice to hear from you after 11 years xD. I attended one of your live sessions like back in 2012

  • @selalekarkon
    @selalekarkon7 жыл бұрын

    Do you have a video on markovnikov's?

  • @Leah4sci

    @Leah4sci

    7 ай бұрын

    You can find resources on that and more at leah4sci.com/syllabus

  • @OrgoMadeEasy
    @OrgoMadeEasy11 жыл бұрын

    Love your method of explaining the mechanisms, I actually make Orgo videos as well. I really wish I had more time to put more videos up sometimes haha. Good luck with your future videos! =]

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    You've come a long way since then!

  • @renuangira7024
    @renuangira70243 жыл бұрын

    My daughter is struggling with o chem . As I liked the way you have explained in the video. I would like to know if you tutor her

  • @Leah4sci

    @Leah4sci

    3 жыл бұрын

    Glad you enjoyed the video. I saw you email, did you get my reply?

  • @bilal1293
    @bilal129310 жыл бұрын

    I think you should reorganize your videos in the order things are taught in organic chemistry course because at the moment relevant videos were difficult for me to find. For example, the first part of your videos could be alkanes, chair formations, e-z, resonance, etc. Then the second part, could be alkenes, alkynes, mechanisms, NMR/IR stuff, Markovnikov, etc. If you do that, I think you could increase your views significantly.

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    While I haven't done that, you can use leah4sci.com/syllabus to help find my resources in order of the typical semester.

  • @mutintachibala7097
    @mutintachibala70974 жыл бұрын

    And can you also explain how we can expand the ring from 5 to 6 carbons using hydrohalogenation

  • @Leah4sci

    @Leah4sci

    7 ай бұрын

    A 6 carbon ring is most stable and so the intermediate will rearrange to give you the more stable version

  • @heenamansuri8848
    @heenamansuri88486 жыл бұрын

    Hi Leah, When doing an ionic addition to an alkene, how do you know when you will have a racemic mixture?

  • @Leah4sci

    @Leah4sci

    6 жыл бұрын

    I'm sorry, but I don't offer tutoring through KZread comments. For help with questions like this and more, I recommend you join the organic chemistry study hall. Details: leah4sci.com/join

  • @ashwinvasudevan7138
    @ashwinvasudevan7138 Жыл бұрын

    Would you also take into account stereochemistry when it is a chiral carbon? So for the HCL & HI example there would be two major products?

  • @Leah4sci

    @Leah4sci

    Жыл бұрын

    Yes, you could. The hydrohalogenation reaction produces a racemic mixture of syn and anti products. One stereochemical configuration is not preferred over the other. Showing both stereoisomers as products would be completely okay.

  • @jyotitangri6662
    @jyotitangri66625 жыл бұрын

    Ma'am in the last example that you explained in this video. Isn't the benzyl carbonation more stable than the 3° carbonation? So shouldn't the Br go to the c attached to the 3° carbonation.

  • @Leah4sci

    @Leah4sci

    5 жыл бұрын

    At which specific point in the video? (Timestamp please)

  • @munawermuhazin5594
    @munawermuhazin559410 жыл бұрын

    I love you Ms. :)

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    Aww thanks!

  • @hassanmustaphaa6643
    @hassanmustaphaa66434 жыл бұрын

    the last example is both regioselectivity and stereoselective

  • @Leah4sci

    @Leah4sci

    8 ай бұрын

    At which time in the video? Hydrohalogenation is regioselective in that the product follow's Markovnikov's rule where the incoming nucleophile adds at the more substituted position. This reaction is NOT stereospecific given that it undergoes a carbocation intermediate. Since carbocations are sp2 (flat) the incoming nucleophile can attack from either side giving you a racemic product

  • @amandeepbaghiana4510
    @amandeepbaghiana45103 жыл бұрын

    At 2:10, when a halogen gets a full octet, shouldn't the formal charge be zero?

  • @Leah4sci

    @Leah4sci

    2 жыл бұрын

    No, the formal charge is -1 here. Halogens have 7 valence electrons, and when they gain a full octet, their formal charge is calculated by saying: 7 - 8 = -1 To learn more about formal charge, read about my shortcut at leah4sci.com/formal-charge-formula-and-shortcut/

  • @adrianamendoza2835
    @adrianamendoza28354 ай бұрын

    What video can I watch to help me identify what is the primary carbon and tertiary carbon?

  • @Leah4sci

    @Leah4sci

    4 ай бұрын

    I have a trick for classifying primary, secondary, and tertiary carbons in a molecule. You can find the relevant video on my tutorial at Leah4sci.com/Pencil

  • @mercychomba7563
    @mercychomba75632 жыл бұрын

    How are the able to identify which carbon is tertiary, secondary or primary on the starting material

  • @elizartstudio

    @elizartstudio

    2 жыл бұрын

    its how many carbons attached to it. Basically 3 lines (makes it looks like a stick person without arms) tetiary (means 3 carbons). Double bond with a line? (its only technically 2 lines. secondary (2 carbon)). triple bond with a line attached.. guess what its still just two lines attached (secondary). Is it a part at the end with only one line but nothing on the other side? (that is primary carbon)

  • @Leah4sci

    @Leah4sci

    2 жыл бұрын

    I have a great trick for this, which you can find on my site at leah4sci.com/pencil-trick-for-classifying-primary-secondary-and-tertiary-carbon-atoms/

  • @eman4159
    @eman41594 ай бұрын

    Where can I find alkene preparation reactions?

  • @Leah4sci

    @Leah4sci

    4 ай бұрын

    I cover alkene prep reactions in various videos. See my alkene series and my SN/E series

  • @tamarangambi8983
    @tamarangambi8983 Жыл бұрын

    ❤❤

  • @Leah4sci

    @Leah4sci

    Жыл бұрын

    Thanks for the positive feedback!

  • @nandini2040
    @nandini20404 жыл бұрын

    8:11 won't there be a ring expansion?

  • @Leah4sci

    @Leah4sci

    8 ай бұрын

    If the carbocation forms on the primary carbon NEXT TO the ring then we have an option for ring expansion. However in this case there's nowhere for the carbocation to go and so the ring remains as 5 carbons

  • @hannikadafnegarzasalazar3191
    @hannikadafnegarzasalazar31915 ай бұрын

    i didnt understand why on the second example, the hydrogen went to the secondary carbon and then, on the cyclohexane example, the hydrogen went to the secondary and not the tertiary

  • @Leah4sci

    @Leah4sci

    5 ай бұрын

    We want to focus more on the position of the carbocation rather than on where the hydrogen goes. We want to form the more stable carbocation intermediate for a Markovnikov product. In the second example that begins at 2:50, the hydrogen is placed on the primary carbon, so that the carbocation formed is secondary. In the final cyclohexene example, the hydrogen happens to be placed on a secondary position, so that the more stable tertiary carbocation can be formed. For more on carbocation stability, make sure to see my tutorial at Leah4sci.com/carbocation

  • @barerahasan7487
    @barerahasan74876 жыл бұрын

    is this anti or syn addition?

  • @leahgreene5880

    @leahgreene5880

    6 жыл бұрын

    Both. It's not stereoselective and will form a racemic mixture of products.

  • @Leah4sci

    @Leah4sci

    6 жыл бұрын

    I cover this in my alkene cheat sheet: leah4sci.com/alkene-reactions-overview-cheat-sheet-organic-chemistry/

  • @916213
    @9162134 жыл бұрын

    at 8:00 where did the Hydrogen go to?

  • @Leah4sci

    @Leah4sci

    4 жыл бұрын

    The less substituted carbon as explained in the video

  • @gonitulislam2284

    @gonitulislam2284

    2 жыл бұрын

    @@Leah4sci mam , is it possible that , hydrogen leave from 1 degree carbon . Because if i do that , ring expansion is possible . And 6 member ring is more stable than 5 member ring . So , leave the hydrogen from 1 degree carbon is more favourable or not . Thank you mam And sorry for my bad English