Allylic/Benzylic Bromination With N-Bromo Succinimide (NBS)

[@AdamsAppleseed]

Man, this is amazing timing for my test tomorrow. Thanks as always Dave! You da real MVP helping me through organic chemistry.

[@PunmasterSTP]

I know it's been awhile, but how did your test go?

[@AdamsAppleseed]

​@@PunmasterSTP I survived. Although chemistry isn't my strongpoint, I enjoyed learning from here.

[@PunmasterSTP]

@@AdamsAppleseed I'm glad to hear it! How are your studies going, or did you already graduate?

[@AdamsAppleseed]

@@PunmasterSTP Graduated! Studying mechanical engineering now :)

[@PunmasterSTP]

@@AdamsAppleseed I'm glad to hear it!

[@DrNothing23]

"Allylic/Benzylic Bromination With N-Bromo Succinimide"... NEVER clicked on a link faster!

[@muditgaur2779]

True bro

[@beaestellagamboa]

Same

[@dukeydanger230]

Thank god for this video, we didn't do an example with NBS in class and the homework has about 15 problems with it! I was so confused, this really helped!

[@prashant4799]

In which grade were you 2 years ago?

[@selenophile6688]

Give this man a Oscar..he deserves this.. Huge respect towards you Sir 🙏👏🏻

[@Grove-StreetHome]

Are you in class 11th?? Preparing for which exam?

[@selenophile6688]

@@Grove-StreetHome why you asked this!

[@bryanu1737]

He knows a lot about *TNT* , Professor Dave explains!...BOOM

[@Luca-wt4dn]

Why doesn't radical dibromination occurr, giving the same product of a thermal dibromination? If you look at the Bond Dissociation Energies, you have (kcal/mol): C=C pi bond = 65 C-H allylic sigma bond = 85 C-Br sigma bond = 68 C-Br allylic sigma bond = 50 H-Br sigma bond = 88 The mechanism here implies: 1)C-H abstraction by radical Br (-85 + 88 = +3) 2)C-Br allyl sigma bond formation (+50) Total = 50+3 = 53 kcal/mol With a hypothetical radical dibromination you would have: 1) C=C pi bond breaking (-65) 2) 2 C-Br sigma bond formations (+68*2 = +136) Total = -65+136 = 71 kcal/mol The two pathways should at least compete, but why does only allylic bromination happen while radical dibromination doesn't? I guess some kinetic effect plays a role, maybe affecting the pre-exponential term of the arrhenius equation and slowing down the hypotetical radical dibromination

[@dieholdfoundation6705]

Dave, what is your educational background? I am curious, and why did you get into this business?

[@fisikan2079]

Yeah I want to know also

[@joeferdin9871]

He has a seperate playlist for misc. questions and also about his education,music turn,etc.

[@fisikan2079]

@@joeferdin9871 amazing

[@NapaCat]

Ah yes, Doug. What's _your_ scientific background? Making false predictions using a bible? Diehold is pathetic. 'Give a competent rebuke' is too much to ask from you.

[@jamesprince571]

1:36 where is hydrogen on nitrogen in succinimide??

[@tetekofa]

"Professor" Dave is a fraud. He doesn't have a clue.

[@thomasneal9291]

@@tetekofa you know, since this is a commercial channel, I'd love to see Dave sue you little asshats for libel. he certainly CAN.

[@heheboiii6285]

I am pretty sure its implied so it needn't be actually shown everytime.

[@jamesprince571]

@@heheboiii6285 we have to put Hydrogen if it's a hetero atom, if carbon it's understood

[@heheboiii6285]

@@jamesprince571 Idk man,maybe the professor forgot to do that🤔

[@chemistfatimasmartscientis3923]

Hi I am a twelve year and I was amused by you vedio too much and I knew it!!!!

[@chemistfatimasmartscientis3923]

@@Buddytwogun No, I am a genius kid that makes these for person

[@chemistfatimasmartscientis3923]

@@Buddytwogun !!

[@chemistfatimasmartscientis3923]

@@Buddytwogun Really don't say that🌻

[@chemistfatimasmartscientis3923]

@@Buddytwogun 🌷🍊🌷

[@PunmasterSTP]

It's kind of an odd experience scrolling through the almost entirely positive comments to see a few flecks of vitriol that are completely ridiculous. For my own part, I'll say thank you professor, for both these videos and for your service to the larger scientific community!

[@muditgaur2779]

Thank you sir Love from India❤️❤️❤️❤️❤️❤️❤️

[@treysternamnam7577]

That hair style is bangin brotha!!! Preciate you as always!

[@zaminahmed297]

Hey professor Dave, just curious did you ever get the master degree that you wanted? Really a huge fan of your channel and videos on organic chem

[@ProfessorDaveExplains]

Yep, I got the MA in science education in 2018.

[@PunmasterSTP]

@@ProfessorDaveExplains I'm just curious, and please forgive me if you already mentioned this somewhere or it's too personal, but what are you up to outside of KZbin these days?

[@ProfessorDaveExplains]

Not much honestly, this is quite the full time endeavor. But I am working on getting way ahead on the content so that I can return much of my energy towards music this year.

[@PunmasterSTP]

@@ProfessorDaveExplains Oh that's awesome, and I feel honored that you replied! I hope your music goes well.

[@EthnobotanikFAQ]

I‘ve seen NBS used to brominate aromatic compounds with allylic positions on the ring, eg in para substitution to the allylic carbon you had pictured. Is it factors like the reaction solvent that determines its reactivity?

[@Felixkeeg]

NBS functions as a "Br+"-equivalent. Without bromide ions there is no bromine formation and thus no radical reaction. Core bromination is therefore a result of an nucleophilic attack of the aromatic ring on the bromo-cation. You will need a base to deprotonate the resulting sigma complex.

[@khushisingh8827]

Thanks proff. Dave to explaning in such a smarter way

[@mrunali3306]

Thank you so much. I really needed this! I understood the concept 💜

[@tohi2302]

Please do a response video to the response video from Pierre!!! This time without your childish insults !!!

[@ProfessorDaveExplains]

There's nothing to respond to, slick. Why are you whining about it in a chemistry tutorial?

[@thomasneal9291]

Fuck off already you pierre psychos. You don't know shit about shit. You're embarrassing yourselves and wasting everybody else's time just by having to scroll past your inanity.

[@NapaCat]

Ah yes, Ben. Give you more of a platform with another video on your protege? No thanks.

[@amnazulfiqar9621]

Thanks alot sir...to summarize that information in conceptual way

[@amanadleshorts7429]

Nice explanation

[@lovenature8766]

Proff dev that's a lot ... I want to know does you make only video for us studying informally or are you getting formal education from each subject. It mean I want to know your history and sucess in every science subject ..that helps to motivates me...plz reply

[@ProfessorDaveExplains]

check out "ask professor dave #2"

[@khushijain9668]

Hey professor. This is out of topic but can you please make a series on physical chemistry including topics like chemical kinetics, electro chemistry, solutions, gaseous state , equilibrium etc etc... PLEASEEEEEEEEE????

[@khushijain9668]

Btw congratulations on 1million subs🥺❤️

[@ProfessorDaveExplains]

Well I covered all of that in my general chemistry playlist, but perhaps one day I'll go into more depth.

[@janellemosquera6335]

pop off professor, you stay educating us :D

[@Thaumius]

is this the first organic chemistry lecture to not feature your whiteboard?

[@Blubb5000]

Finally a topic that is important for everyone to know all about it. (What the hell was he even talking about?!? I know some of the words he said... but not in this combination.)

[@williamchamberlain2263]

Come on - everyone wants to brominate their alkanes

[@Blubb5000]

@@williamchamberlain2263 I broomed my alcove. Does this count?

[@pfeliciano4062]

dude your hair cut makes you look 10x finer

[@divyanshusingh7287]

Awesome video!!!

[@fisikan2079]

Amazing

[@alfredtovar6451]

Thank you dude! That was qn excellant explaination!

[@ravi86591]

professor, you're amazingg!

[@cherry8735]

What if both allylic and benylic positions are available? Which will be preferred?

[@YashSingh-nx7pb]

Awesome

[@grithelbasnig2500]

Hi Sir. (I know its out of the topic) but please help me to combine valine and lysine, their structures suckkkkkk pleasee

[@PunmasterSTP]

Do you mean "combine" as in a condensation reaction that forms a peptide bond, or in some other sense?

[@ModernEducationYt]

Can you please make videos on electrostatics

[@monikasangwan4466]

From which country you are?

[@glennpearson9348]

Always love your work on chemistry, Professor Dave. Thanks!

[@roshanpatil3078]

thank you 👍👍🙏🙏

[@alirizademir8242]

شكرا مسبقا ❤️

[@sysfailureexe6038]

Thank ü

[@mayabudburgh6084]

Thank you so much

[@rayaazzam7536]

thx this was very helpful

[@devjani4066]

just like ..anti-markovnikov rule...homolysis..radical based reaction

[@backstreetfan2887]

I ❤️ O chem

[@sheri-.-]

🤟 you rock Professor Thanks a lot 😊

[@hiromishimada7200]

damnn just in time for my org chem probset. thanks a lot !

[@PunmasterSTP]

How'd the rest of ochem go?

[@hiromishimada7200]

@@PunmasterSTP i passed it !!!

[@PunmasterSTP]

@@hiromishimada7200 Sweet, I’m glad to hear it!

[@danielpatterson9599]

Dave is eveything wrong with science and physics today. And a know-nothing child attacking the giant that is Pierre-Marie Robitaille. Why, because he thought he that he saw an easy mark for clicks, or was he just humoring his own narcissism? Shame on Dave!

[@ProfessorDaveExplains]

Haha, if you think Pierre is a "giant", then what are actual real scientists? Grow up, slick. Maybe learn some science while you're here, yeah?

[@thomasneal9291]

"a know-nothing child attacking the giant that is Pierre-Marie Robitaille" wow, argument from authority much? yikes.

[@NapaCat]

Run back to Benny for your muffin, bud.

[@whoUthank]

Bullying a modern day Copernicus will be a stain on you one day. Especially when you have to reconcile that you are the scientific equivalent of a flat earther. No need to respond slick, just go do your homework champ. Good talk bud.

[@ProfessorDaveExplains]

Haha, a modern day Copernicus! That's funny, because Pierre isn't an astronomer. Or a scientist of any kind. He's a snake oil salesman. And you fell for it. Do try to avoid commenting on my academic tutorials, as you clearly have no interest in learning science. Ok sport?

[@thomasneal9291]

@Strafe Craft "Good talk bud." I'm not your buddy, guy... kzbin.info/www/bejne/sKa0fGmqZ6qmpMk figured I'd toss something actually worth watching instead of your inane commentary. I know, I know, I didn't NEED to.

[@NapaCat]

Pierre ain't a maverick, an astronomer, or even a scientist anymore.

[@varunij5824]

🙏🏻🙏🏻🙏🏻🙏🏻

[@jhydpumar3244]

thanks professor dave ! the Jesus Christ look alike in Chemistry. Like if you agree haha

[@ayushshukla1042]

:)

[@ModernEducationYt]

1st comment

[@babarazamsucks]

First!