Zaitsev and Hofmann Elimination Products

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9 жыл бұрын

Sometimes you can get multiple elimination products from the same reaction, and we have to be able to name them. Not more nomenclature! Well, yes, kind of. But it's people's names. Zaitsev and Hofmann, to be precise.
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@songohan393 4 жыл бұрын

I told everyone in my oc class about you every single of them are learning with your videos now :D

@ProfessorDaveExplains 4 жыл бұрын

thanks for spreading the word!

@alirezasadeghifar3815 2 жыл бұрын

@@ProfessorDaveExplains me too, they are all your recent subscribers, they love you man!

@sagar1326 5 жыл бұрын

A friend told me about this channel, and what turns out is sir you are underrated.

@rudranshpratapsingh7761 5 жыл бұрын

Sagarnil Chakraborty yeah really.

@CliffStamp 7 жыл бұрын

Dave, appreciate how you explain from fundamentals why one product is favored, not just give some rule which appears arbitrary. This was always one of my biggest problems with Chemistry, it seemed to be a collection of rules with no coherent explanation.

@brightlandwitch 9 күн бұрын

yeah so much gatekeeping lol

@jenniferhernandez2889 5 жыл бұрын

I was feeling discouraged about organic chemistry until I met you!!! Thank you so much for all the work that you do!!! You are a true blessing for all the struggling college students :')

@faal1805 9 жыл бұрын

You are by far with the most clear explanation. Very well done ! U have an extra subscriber today ;-)

@emperorviktor3335 2 жыл бұрын

Thanks Chemistry Jesus

@bigpapaj2611 8 жыл бұрын

You make things so easy to understand; you always explain clearly why things occur. THANK YOU!

@denerrodrigues9417 7 жыл бұрын

Thanks for the quality of your videos! I'm from Brazil and many topics of chemistry, we suffer for not having quality video lessons as yours, thank you!

@sukainaalherz3554 9 жыл бұрын

Thank you very much... you are highly organized when you explain with such great skills in addition to your knowledge that make all of what you said understandable and clear...appreciate your efforts.

@malenaramirez2705 10 ай бұрын

i didn't know i could understand organic chemistry until i found your video, i had to read the subtitles because i speak spanish but i understood everything !! thank you very much

@alaminhossain5348 3 жыл бұрын

Your classes are awesome...my addiction to chemistry is increasing day by day ...thanks a lot sir 😍😍..and I also suggest all of my friends to watch your lectures for clear conception .

@Jisescrait33 3 жыл бұрын

I dont know how i discovered your channel but im happy about that, my mother language is spanish and there's no organic chemistry videos with this quality at least on youtube! keep doing your stuff.

@Jisescrait33 3 жыл бұрын

when i said organic chemistry videos I mean organic chemistry videos in spanish languague

@andersondemori7076 8 жыл бұрын

oh thanks Professor Im from Brazil and your videos are so good, even they are in English.I understood everything about this organic reactions...tks a lot

@miriamramos8873 5 жыл бұрын

love the visual explanation of the chair conformation and why one of the H is not available. You are the best thank you so much.

@gabe2029 5 жыл бұрын

you are very clear at explaining, i will share your videos with my classmates. blessings.

@seanoggilrane4514 2 жыл бұрын

Love how helpful these videos are Professor! Keep up the great work

@shailendrasinghal684 6 жыл бұрын

my professor explained the same topic for 2 to 3 days which u made possible in just 10 mintues...keep up the good work :D

@pranav_manoj 4 жыл бұрын

I cannot thank you enough for the awesome explanation !

@josechemistryintamil11than53 3 жыл бұрын

Wow u cleared my doubts...thank u sir...each and every students ..can understand your teaching....many u tube i watched....but urs very crystal clear..not skipping any small points....thank u sir....from india....

@mehranmoshkelani90 8 жыл бұрын

Thank you so much professor Dave.you are great.

@lucasreddy1118 7 жыл бұрын

sir it's 3-bromobut-1-ene. tanks a lot .. u r the best on KZfaq

@lisadinh 9 жыл бұрын

Thank you professor Dave this cleared up a lot of things for me for my Ochem midterm

@PunmasterSTP 2 жыл бұрын

I know it’s been awhile, but how did your midterm go?

@areejalsham6662 6 жыл бұрын

I always try to find your videos when i study, you are the best ever thanks alot i wish you can do all the chm :(

@aswins2249 Жыл бұрын

That was such a good explanation. Crystal clear.

@njockify 6 жыл бұрын

Thank you so much! I was struggling with this in class and you made everything so clear! thank you

@PunmasterSTP 2 жыл бұрын

How’d the rest of your class go?

@lukehigginbotham2823 6 жыл бұрын

Earned a sub!! Thanks so much for the help man!

@tarandeepsingh5571 3 жыл бұрын

he knows a lot about science stuff. professor dave explains everything!

@depfro 9 жыл бұрын

Very helpful. Thank you very much :D

@Therockingww 5 жыл бұрын

Thank you so much Prof. Dave :)

@katjaschneider5816 2 жыл бұрын

Gutes Video! I did understand it much easier than in the most german OC videos.

@ishankamapatuna5302 9 жыл бұрын

Wow you are done great job sir thank u very much...

@mariamdiab3678 9 жыл бұрын

YOU ARE A LIFESAVER! Thank you :)

@mykalmartin3573 3 ай бұрын

very coherent explanations still relevant for OC

@healthyhappymind542 Жыл бұрын

Thank you so much Prof Dave, for finally making chemistry an interesting learnable system for me.

@mujeebkhan7713 5 жыл бұрын

Thank you so much sir..... It help me a lot

@todayisdomingo 7 жыл бұрын

Lmao, Nice intro, You won a Suscriber, a chemist student from Venezuela :D and thank you!

@ShenelleTaylor 8 жыл бұрын

thanks for the help !

@Anonymous-bz7ij 2 жыл бұрын

thanks sir for this wonderful lecture

@purplefalcony7127 3 жыл бұрын

I can't thank you more, for it's the first time I distinguish Zaitsev from Hofmann. I used to think they are the same person that refers to the same process. And now, I feel I might pass the exam.

@PunmasterSTP 2 жыл бұрын

How’d your exam go?

@purplefalcony7127 2 жыл бұрын

@@PunmasterSTP Of course I passed, and got more than expected marks. Can't thank Dave enough.

@user-zw7po5xj6r 3 жыл бұрын

Why you deal with E2 you should select SN1 because it made us action +3

@djchemtalk2946 7 жыл бұрын

Excellent episode....

@OVERDOSE 8 жыл бұрын

amazing examples!!!! (:

@relaxingnature6438 8 жыл бұрын

good teaching sir

@carlovaldes259 5 жыл бұрын

Thanks , the best explication ever !!

@BRo-it1jh 5 жыл бұрын

Great video!

@Whitedragon1250 2 жыл бұрын

and once again i learned more from a 10 min youtube video than from 1.5h lecture in school

@johnmathew168 6 жыл бұрын

Thank you so much 😊😊😊

@rohithnarahari9018 Жыл бұрын

Actually I was in confusion which will be major product but this sir made my life easier thankyou so much sir

@hanankhalil1106 6 жыл бұрын

Thank u so much🙏

@Itharmomin_Vlogs 5 жыл бұрын

Very well explaination

@scottcampbell1635 25 күн бұрын

Thanks for not just telling me what to do but WHY WE DO IT. My orgo professor is great but we're in an accelerated course so sometimes the "why" is missed. To me, I just can't do the "what" without the "why".

@sachinpatel9372 3 жыл бұрын

By far the best ❤😘

@paoboonjinnz 7 жыл бұрын

thank you!! helpful

@quintonanderson5980 5 жыл бұрын

Thank You!!

@prashantyadav7272 3 жыл бұрын

This video needs to get more views

@yasmineshiraz3844 3 жыл бұрын

thank you so much

@MilitaryPoliceG795 Жыл бұрын

How can you have tetrasubstituted? Wouldnt there not be a beta hydrogen to produce the double bond?

@saimahmad4980 4 ай бұрын

Thanks sir

@chimp1143 8 жыл бұрын

EXAMPLE OF NUCLEOPHILIC SUS REACTION 1.REPLACEMENT BY CN- GROUP RX+KCN---->RCN+KX WHEN AgCN IS USED IN THE PRODUCT WE GET RX+AgCN--->RNC+AgX (ISONITRILE) WHY IS THIS SO?

@inderveerchahal185 7 жыл бұрын

God Bless this man

@adityaagrawal5407 2 жыл бұрын

you literally saved my exams!!

@PunmasterSTP 2 жыл бұрын

How did those exams go?

@HarshRajAlwaysfree 4 жыл бұрын

Thanks professor ;)

@zahrajaffary3547 5 ай бұрын

so when do we use saytseff and when hoffman?

@baileyb3050 Жыл бұрын

You are a lifesaver

@jacobc2378 5 жыл бұрын

How am I learning more from a free video than I am from the college class I’m paying $thousands$ for?

@flowerchild7471 8 жыл бұрын

Thanks so much your awesome

@watiskongchanpat3620 2 жыл бұрын

Does the symmetry effect it? (I mean like is only wedge Hydrogen gonna attacked by Nu?)

@robochibi 5 жыл бұрын

Dude you are the best!

@FanOfRobert 8 жыл бұрын

very good video

@haneenal-salihi 3 жыл бұрын

wow ...thank you ... grazie .,,,, شكرا

@xdvfgxngfnf 8 жыл бұрын

Hey Dave, Great videos. Could you possibly do a video showing this kind of problem except where the LG is equatorial and the chair must do a ring flip to do the reaction? Having trouble with that and I know that it will be on my final. Colin

@ProfessorDaveExplains 8 жыл бұрын

+Colin McCorkle i will add it to the list! though it won't be in time for your final. happy to do Skype tutoring if you like.

@colinmccorkle1195 8 жыл бұрын

+Professor Dave Explains Hey Dave, How much do you charge for the Skype tutoring? Colin

@gregoriocallone8330 4 жыл бұрын

Hello Prof. Dave. I'm following these tutorials right now. Very helpful. But sometimes I still have questions, and I dont know if you hang around these videos cause they are quite old. I'll try and ask them anyway. So my doubt about this is, in the examples part of the video, is there a specific reason why you would have us draw the chair for compound number 2 but not for number 1? Isnt that a cyclohexane as well? And isnt the carbon on the left of Br still a potentially working beta carbon? Ty so much man you know what you are doing and you are definately making me interested in the subject. Btw if Prof Dave couldnt answer maybe some1 else will, I would still appreciate the help.

@ProfessorDaveExplains 4 жыл бұрын

For the first one, the carbon on either side has both protons available for elimination, so it is a given that one of them will be in the proper orientation, we don't have to check. With the second, there is a neighboring substituent, so we have to look at the chair.

@rxdsza 7 жыл бұрын

Thank you so much :')

@JaSomAdAm 9 жыл бұрын

Very good video you've done good job man but i got a question. According to reaction when bromcyclohexan is turned into few Hoffman products, as far as kinetics would drive this reaction, will there really be a double bond formed with that atom of Br? I mean wouldnt it rly prefer a double bond creation in the circle? Sorry if my question is explained in ur vid.

@ProfessorDaveExplains 9 жыл бұрын

Adam mackovčin no double bond to bromine! bromine is the leaving group. a double bond will be formed between two carbon atoms.

@meilanycaimares4046 6 жыл бұрын

QUESTION - In the second portion of the video when you're explaining the first example - when the Bromine leaves the molecule why is there a methyl group in the first outcome? There was no carbon there before why is there one now? I hope I'm asking clear enough. Other than that amazing video! Thanks so much.

@ProfessorDaveExplains 6 жыл бұрын

there was a methyl! it's the dash bond.

@siyabongankosi9956 6 жыл бұрын

A legend describes what you are

@H.Mark. 6 жыл бұрын

Oh my God! I understand why for the first time in my life!

@Anna-dc5oi 9 жыл бұрын

where would the stability of an alkene with two methyls on one carbon and 2 hydrogens on the second carbon rank among these? (CH3)2-C=C-(H)2

@ProfessorDaveExplains 9 жыл бұрын

Anna Kornak that would be a disubstituted alkene, i'm guessing because of sterics it would be less stable than trans-2-butene, and somewhat comparable to cis-2-butene, though i'm not sure with absolute precision whether it would be slightly more or less stable than cis-2-butene. i'll go ahead and guess slightly more stable since double bonds are shorter than single bonds.

@isabellaswan6905 2 жыл бұрын

tHIS dude's a literal saviour

@sowmyakotha2435 4 жыл бұрын

Tq. Sir

@annica999 Жыл бұрын

is zaitsev and saytzeff the same person?

@randomstuff4092 4 жыл бұрын

great Sir :-)

@prasadkulkarni7686 5 жыл бұрын

Why did you put isopropyl group above?? What if ring flips?? Do we get same or different products??

@ProfessorDaveExplains 5 жыл бұрын

that's the conformation from which E2 proceeds

@shanemichael9011 5 жыл бұрын

I love this well understood video and the ones on historical figures too. They are great Prof. Dave ! Anyway, while viewing this Hoffman/Zaitsev video I found it informative, but out of curiosity, I always wondered why the lone hydrogen attached to the Carbon holding the Halogen itself is never involved in any reactions where bases are grabbing protons. They only go after hydrogens on nearby Carbons. I would assume that there is one there since stable Carbons have 4 bonds. Maybe I am missing something.

@ProfessorDaveExplains 5 жыл бұрын

good question! so the proton on the carbon that bears the halogen is not acidic, because if a base grabbed it, where would the resulting negative charge go? it would be localized on the carbon. only if a beta proton is abstracted can a pi bond form because it is the leaving group that is able to leave.

@shanemichael9011 5 жыл бұрын

@@ProfessorDaveExplains Thanks so so much. I am a Man who always loved learning about what some people would call "the craziest things" !! Science is my favorite and my burning desire to learn is still with me even though my childhood days are many years gone. Thanks again Prof. Dave And for the informative videos ! ☺

@harveyalram5393 Жыл бұрын

This guy is the goat

@icemabubobub1578 Жыл бұрын

Shouldn't the isopropyl at 08:30 prefer the equatorial comformation ?

@ProfessorDaveExplains Жыл бұрын

yes but elimination can't proceed from that chair

@ashleechadwick6392 7 жыл бұрын

So I know when there is a tert-butyl group and you draw it in chair form, the tert-butyl is always in the equatorial phase. Why is the dimethyl drawn axial? (or does it not really matter?)

@ProfessorDaveExplains 7 жыл бұрын

every chair has two conformations, and every substituent on the chair will be axial in one conformation and equatorial in the other.

@jonasmarqua5994 7 жыл бұрын

Yes i had the same question...there are 3 substituents all in axial position....wouldnt it be too much unfavourable to switch to that position for the ring ? wouldnt it be almost as an anchor if you got 3 substituents in equatorial position ?

@lucasyoshida1235 4 жыл бұрын

isn't the isopropyl in the axial position going to make this conformation reaction unfavorable and a slower reaction? Therefore having to do the reverse chair?

@ProfessorDaveExplains 4 жыл бұрын

but the leaving group must be axial, so it must be in that conformation, which means it will just be a slow reaction

@danielohearn5408 6 жыл бұрын

Is there a mathematical relationship between the Hoffman and Zaitsev product distribution and the molecular weights of the bases?

@ProfessorDaveExplains 6 жыл бұрын

not reliably, i wouldn't think, as it's all about sterics, and although lighter bases are usually less sterically hindered, that isn't a rule by any means.

@allesklar8636 3 жыл бұрын

Greetings from Germany :) love these videos

@rrezartkrasniqi5578 3 жыл бұрын

du bist ein Ehrenmann

@lucasreddy1118 7 жыл бұрын

sir what if 3-bromobut-ene undergoes elimination with koh?will it follow zaitsev rule?

@ProfessorDaveExplains 7 жыл бұрын

where is the double bond? if it's internal you'll get the alkyne. if it's terminal, you'll get the conjugated diene. actually i suppose it must be terminal otherwise it would have to be 2-bromo, so yes you'll get the alkyne which i suppose would be considered the zaitsev product, although i don't think we would apply that nomenclature in that particular instance.

@PunmasterSTP 2 жыл бұрын

Hoffman? More like “You’re the man!” 😎

@kirstenyu9258 5 жыл бұрын

Bless you my angel

@Surya045_ 3 жыл бұрын

Thank u sir❣️from india

@nikhilchaturvedi5537 3 жыл бұрын

Nice

@carlosjenkins7882 9 жыл бұрын

Why didn't you apply the anti-co planar rule to the first reaction..considering that they are both ring structures?

@ProfessorDaveExplains 9 жыл бұрын

Rick Jenkins for that first ring i use the protons on either side that are anti coplanar to the leaving group, i just didn't examine the chair structures to prove it, since i went over that extensively in the "E2 on cyclic structures" clip.

@carlosjenkins7882 9 жыл бұрын

Professor Dave Explains Thanks for the response. You have gained another subscriber!

@michaelwiles5363 6 жыл бұрын

In the first example (9:00min onwards) why is the dashed hydrogen the one that gets eliminated for the Hoffman product? I thought that the proton that gets eliminated needs to be on an adjacent carbon and anti to the leaving group? thanks! :)

@ProfessorDaveExplains 6 жыл бұрын

at the end with bromine and methyl on cyclohexane and methoxide going to zaitsev and hoffman? that proton is not on the dash, the methyl is on the dash! three hydrogens are on it, one will be anti at any given time.

@michaelwiles5363 6 жыл бұрын

Sorry! my bad! I meant 6:00min. I have no idea why I put 9min. Its the first (top) example of two that you do. Thanks for coming back to such an old video. Im sure the answer is straight forward but I just cant see it :)

@remesweet62 Жыл бұрын

Thinks

@DF-il4uu 8 жыл бұрын

In germany we call it Saytzeff and Hofmann product. That's weird because they're actual names.

@manavshah6811 8 жыл бұрын

Russian translation can be awkward and vary in various books and authors

@HrishikMukherjee 7 жыл бұрын

Same in India !

@aayushsharma3655 5 жыл бұрын

fellas the rule is called Saytzeff rule which was given by chemist Zaitsev.....so nobody is studying different

@avijitdey992 5 жыл бұрын

@@aayushsharma3655 no. It is Saytzeff/Zaitsev/Saytzev's rule depending upon which language you speak. Zaitsev was his name in Russian but his English name spelling was Saytzeff and our education system is adopted from English thus we also call it Saytzeff rule. Open a Russian authored book and you'll see it as Zaitsev's rule.