why do so many o.chem books leave out the ring expansion topic when they teach alkene mechanisms? Thumbs Up Ms. Fisch! Thanks for the explanation.

@sanchithuehuehue

3 жыл бұрын

Literally every book man, I couldn't find this anywhere, not even clayden.

@joeygallo-rodriguez2114

2 жыл бұрын

I read my textbooks reaction mechanism chapters from start to finish and didn’t find anything about it! You could then imagine my disappointment when I saw a question similar on my practice exam.

@shadowkxm

10 ай бұрын

so they can screw you in the exam

@Leah4sci

5 ай бұрын

So happy I could help!

Ah... Finally the rearrangement makes sense. Very succinctly explained. Thanks

@Leah4sci

5 ай бұрын

Woohoo!!! So glad to help clear it up for you!

I watch your one of your videos every night before I go to sleep. Very enjoyable, no pressure, easy to understand. I choose to watch the video that's related to the material I study on that day. I don't have to worry about ochem exams anymore. Truly appreciate your work!

@Leah4sci

7 ай бұрын

Oh wow, that's awesome to hear, thank you!

Thank you sooooo much Leah! You're literally a life saver! So happy I found you:)

@Leah4sci

6 ай бұрын

Awww you're so welcome!

An amazingly clear explanation! You're a phenomenal teacher! Thank you! :)

@Leah4sci

7 жыл бұрын

You're very welcome! Glad it helped!

Finally a tutorial which actually helped me. Everyone was just skipping over the most confusing part - where the carbocation was supposed to be placed after ring formation.

@Leah4sci

3 жыл бұрын

Happy to help!

My gosh! This was awesome--Thank you!

@Leah4sci

6 ай бұрын

You're so welcome!

Absolutely simple and easy to understand , please be encouraged to make more of these.

@Leah4sci

4 жыл бұрын

Glad you enjoyed it!

LEAH YOU ARE JUST AMAZING AT THIS EXPANSION EXPLANATION. GOOD JOB KEEP IT UP.!!!!!

@Leah4sci

7 жыл бұрын

Thanks for your kind words. I'm glad you like it!

Thank you for explaining this so clearly! The ring expansion was driving me nuts!

@Leah4sci

6 ай бұрын

You are very welcome!

Simple explanation, awesome. I have an amazing professor but he's a Harvard double grad genius who's so smart he doesn't realize he lectures extremely quickly. The ring alkyl shift had me perplexed this whole time but now it's obvious, thanks!

@Leah4sci

5 ай бұрын

Yes, that's common for people that are so intelligent. Sometimes they don't know how to break it down enough. Glad I could help!

Extremely thorough and helpful, thank you !!

@Leah4sci

5 ай бұрын

You're very welcome!

Very nice 👌👍👏 explaination mam I was pretty confused in this topic before watching 👀 this. Now I have understood. Thanks from a neet aspirant from 🇮🇳🇮🇳

@Leah4sci

2 жыл бұрын

Glad to hear that! you're so welcome!

@jsintar4473

2 жыл бұрын

@Naveen praveen yes

Excellent. You have been and also be the best at what you do.

@Leah4sci

Жыл бұрын

Thank you so much. I appreciate the compliment!

OMG!!!! this helped sooo much! Thanks for the video!

@Leah4sci

6 жыл бұрын

You're very welcome

Thank you so much I had a ring contraction problem and this was the only thing I could find to help me solve it

@Leah4sci

3 жыл бұрын

Glad I could help!

Thanks so much, it really helped!

@Leah4sci

2 жыл бұрын

You're so welcome!

Thank you so much. I now have an idea through your tutorial. You are an amazing teacher!

@Leah4sci

5 ай бұрын

You're so very welcome, happy to help!

Thank you so much to understand the rearrangements in carbocations in easyway

@Leah4sci

6 жыл бұрын

You are welcome!

Oh.. Thank you mam... I'm searching for a long time to get a clear answer for this

@Leah4sci

5 жыл бұрын

Glad you found your answer! You're welcome! :)

This helped me so much, Thank you!

@Leah4sci

6 жыл бұрын

You are welcome!

Thank you so much Ma'am!

@Leah4sci

3 жыл бұрын

You are so welcome!

just loving you, thksss a lot from Brazil

@Leah4sci

7 ай бұрын

You're welcome!

Amazing mam...iam from India and I had problem with such kind of mechanism....ur explanation was magnificent....

@Leah4sci

3 жыл бұрын

Aww, thanks for your kind words!

Nice work you diserve nobel award from ethiopia 👏👏🇪🇹🇪🇹🇪🇹

@Leah4sci

2 жыл бұрын

Awww, thanks!

SOOOO much helpful. Thanks!

@Leah4sci

3 жыл бұрын

Glad it was helpful!

Amazing explanation. I just have one question. At 2:22, you chose to break that bond to shift it over. What if you chose the right side of the cyclo butane. When I tried doing this myself, I got 1,3-dimethylcyclopentan-1-ol. I am not too sure if we can do it like this though. Did you arbitrarily pick that bond of the cyclobutane? Thank you!

@sambhavnapati3313

3 жыл бұрын

Not really sure but ........ the bond on the left is broken may be because it's more unstable due to the alkyl grp connected to it .

@Leah4sci

3 жыл бұрын

Yes, it was an arbitrary decision to break the bond on the left. The situation that you have laid out is a viable alternative to the mechanism in this video. It is very likely that the product mixture of this particular reaction would contain a large percentage of 1,3-dimethylcyclopentan-1-ol.

thank you maam.With My competitive exams approaching, this doubt clearing was essential

@Leah4sci

5 жыл бұрын

You're welcome. All the best on your exams! :)

Thank you so much, you are a great teacher.

@Leah4sci

7 ай бұрын

You're very welcome!

this helped SO much, thanks!

@Leah4sci

5 ай бұрын

You're very welcome, happy to help!

Loved it!!!! 😍

@Leah4sci

3 жыл бұрын

Awesome!!!

Awesome video. Thank you very much.

@Leah4sci

7 ай бұрын

You're welcome!

I liked it. I am a retired chemist and really enjoyed your presentation. I intend to embed it in a simple article I've written.

@Leah4sci

4 жыл бұрын

Sure thing, just make sure to site the source!

@KuznVinny

4 жыл бұрын

@@Leah4sci The embedded video would have done that by nature. It would simply have brought the individual back here. But I've decided not to write the piece.

Thanks a lot for clearing my concepts.

@Leah4sci

5 ай бұрын

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

a very good expanation of the concept! Amazing teacher! do u hve a video on sn1 , sn2 and neighbouring group participation(NGP) substituion reactions??

@Leah4sci

5 ай бұрын

Glad to help! You can find all of my resources here: leah4sci.com/syllabus

THANKS I LOVE YOU YOU'RE A LIFE SAVER 💞💞💞💞💞💞💞

@Leah4sci

7 ай бұрын

Aww you're so welcome!

Thank you so much

@Leah4sci

Жыл бұрын

you're so welcome

You save my chemistry!Thanks a lot. Student from Taiwan.

@Leah4sci

4 жыл бұрын

Happy to help!

this helps by a lot

@Leah4sci

Ай бұрын

Glad it helped you!

Thanks a lot mam for making it easier

@Leah4sci

3 жыл бұрын

You're very welcome 😊

Thanks for that great video

@Leah4sci

5 ай бұрын

You're welcome!

Thank you so much!!!!

@Leah4sci

6 ай бұрын

You are so welcome!

Thanks a lot ma'am.

@Leah4sci

8 ай бұрын

You're welcome 😊

that was amazing thanks a lot ! :)

@Leah4sci

6 ай бұрын

You're very welcome!

THANK YOU SOOOOO SOOOO SOOOO MUCH!!!!!

@Leah4sci

6 ай бұрын

You're so very welcome, happy to help!

Could not understand ring expansion earlier...Not anymore... Big thanx to u 😊😊

@Leah4sci

6 жыл бұрын

Glad I could help!

Very good explanation ...

@Leah4sci

3 жыл бұрын

Glad you like it!

Thanks Leah you da man

@Leah4sci

5 ай бұрын

You're welcome!

Thank u so much

@Leah4sci

2 жыл бұрын

You're very welcome!

thank u so much ...very helpful

@Leah4sci

5 ай бұрын

You're very welcome!

Exactly my doubt! thanks a lot ;)

@Leah4sci

5 ай бұрын

You're so welcome!

Thanks for the video

@Leah4sci

5 ай бұрын

You're welcome!

Thanks again!! :)

@Leah4sci

5 ай бұрын

You're so welcome!

Really it's osm explanation...love from India 🤗🇮🇳🇮🇳

@Leah4sci

2 жыл бұрын

Glad it helps!

Outstanding explaination

@Leah4sci

7 жыл бұрын

Glad you enjoyed it!

IT ALL MAKES SENSE NOW

@Leah4sci

4 жыл бұрын

Awesome!!!!

awesome and simple

@Leah4sci

6 жыл бұрын

You are very welcome!

Question: can we have 2 ring expansion product depending if there is a bond between left or right carbon and if so what is major ?

@Leah4sci

4 ай бұрын

Yes, that would be an option, as for major... I don't know as this would have to be measured in a lab

Thank you!

@Leah4sci

5 ай бұрын

You're very welcome!

Very good 😊

@Leah4sci

Жыл бұрын

Thank you!

THANK YOU

@Leah4sci

5 жыл бұрын

You're welcome :)

Nice explanation

@Leah4sci

4 жыл бұрын

Glad it helped!

can this allow a primary carbocation to form, i just got a ring expansion question on an org exam but the leaving group was attached to a primary carbon. It's been a mantra throughout the course that primary carbocations are too unstable and dont form, so it dosnt make any sense

@Leah4sci

2 жыл бұрын

Primary carbocations should NOT form without resonance to stabilize the charge

my question is : you choose to break the bond above to do the shift but what if I choose to break the one underneath -H ( red pause 2:25), will i get the same product? i've tried it but it i don't get the same :(

@superb7319

6 жыл бұрын

probably wayy too late; i tried what you said, and i get the same product ( my product is just flipped over, makes no difference however ). Nice question however ^^

@Leah4sci

4 ай бұрын

It didn't occur to me. Yes you're right, we have the potential for a constitutional isomer

This really helped me alot! But from that example , is it possible to have an alkyl shift?? If yes, could you upload a video for that?

@Leah4sci

Жыл бұрын

Glad it helped! Yes, it is definitely possible to have an alkyl shift. The mechanism for this is explained here: kzread.info/dash/bejne/lYeLm659qNfbn6Q.html

Thanks cleared my concept

@Leah4sci

5 ай бұрын

So happy to help!

thanks a ton..!!!!

@Leah4sci

7 ай бұрын

You're welcome!

I love you!!

@Leah4sci

7 ай бұрын

Thanks!

huggggggggggggggggggggg* thanks you!!!! helped me a lot!!

@Leah4sci

5 ай бұрын

You're very welcome!

I understand what you did but there is a something I did not get it that HOW CAN I KNOW WHEN I SHOULD EXPAND THE RİNG??? THANK YOU SO MUCH!!

@Leah4sci

3 жыл бұрын

You're very welcome! Ring expansion is favorable when it produces a more stable, 5- or 6-membered ring. Remember that 6-membered rings are THE most stable and “happy” cyclic structures. 5-membered rings are also preferable to smaller ones.

respect !!

@Leah4sci

5 ай бұрын

thanks!

My mind.....wow!

@Leah4sci

5 ай бұрын

Thank you!

Omg this is so fun! I want to solve more of these can someone tell me where will I get such problems?

@Leah4sci

4 жыл бұрын

Awesome! Glad you love it!

@phenomenalphysics3548

4 жыл бұрын

@@Leah4sci all thanks to you

What would happen if we did do a hydride shift earlier for the last problem?

@Leah4sci

3 жыл бұрын

If you’re speaking of the decision to expand the ring, it was MORE preferable for the alkyl shift (ring expansion) to proceed because of the large increase in stability that a 5-membered ring provides. The hydride shift to form a tertiary carbocation on the cyclobutane does not happen in place of the ring expansion.

Why doesn't the bond on the right of the square break instead of the top of the square? How do you know which bond will break?

@Leah4sci

Жыл бұрын

That's a great question! In actuality, either bond can break, leading to a mixture of possible products. My KZread videos are only brief overviews of these concepts. For in depth help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

wow..thanks ..i always had difficulties with this..thxx a lott...n keep uploading...any suggestion for a good book on organic chemistry..

@Leah4sci

5 ай бұрын

You are so very welcome, happy to help! And you can find my top pics for orgo here: leah4sci.com/5-must-have-organic-chemistry-resources/

From the structure, it seems like carbocation should be on C1. How do we know it's on C5 after the ring expansion?

@Leah4sci

2 жыл бұрын

Look at which carbon lost a bond and got nothing back in return

I had one qn like this during my test and I screw up in it.( which is worth like a lot of marks) but Thanks to yur video, I now understand hw to tackle such qns. Even though its kind of late for my test but its good for my final exam. :)

@Leah4sci

5 ай бұрын

I'm so glad I was able to help you understand this for your final!

How do you know when you substitute with hydrogen or make a ring expansion ?

@Leah4sci

7 ай бұрын

If you have the option to create a more stable ring, ideally 6 C from 5 or 7, you'll get a ring expansion or contraction

Do you have any videos on Alkynes reactions?

@Leah4sci

5 ай бұрын

You can find that and more using my free syllabus guide: leah4sci.com/syllabus

helpful !!!

@Leah4sci

7 ай бұрын

Great!

Very nice! Thank you. *subscribes*

@Leah4sci

5 ай бұрын

You're very welcome and thanks for subscribing!

Amazing explanation ma'am. I have a doubt can u please help me out " If a carbocation have two possibilities one is rearrangement and 2nd is internal ring attack,what would happen " eg. If 1-chloro-2-methyl-4-(meta-toluine) butane +AlCl3 ------> what's the final product , please please if possible answer my doubt 🥺🥺🥺 , waiting

@vijay-thala-fan

Жыл бұрын

Maybe IUPAC of compund I had written was incorrect it can be " 1-chloro-2-methyl 4-(3-methyl phenyl) butane " maybe it's correct IUPAC

@Leah4sci

Жыл бұрын

I'm sorry, but I don't offer tutoring over social media. For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

great video .... and ..can there be two ring expansions in any possible way could the cyclopentane ring expand to cyclohexane cuz cyclohexane is the most stable acc. to baeyer's strain theory

@vaddadisairahul2956

8 жыл бұрын

according to buyers strain theory, six membered ring is more stable so 7 membered ring will undergo contraction to 6 membered ring and by the way a 4 membered ring will convert to 5 membered ring only and similarly a 5 membered to 6

@vaddadisairahul2956

8 жыл бұрын

+v sai rahul vaddadi sorry bayers

@Leah4sci

Ай бұрын

Thank you! As the other comments already said, six is ideal

Why did oh- attack tertiary carbonation and not secondary. Isn't tert carbonation more stable?

@Leah4sci

3 жыл бұрын

Yes, tertiary carbocations are more stable than secondary. That is exactly why the tertiary one is present when the water molecule comes in to attack. It is so stable that the hydride shift happens almost instantaneously in this reaction to produce the more stable tertiary intermediate (rather than having the secondary carbocation persist).

Nyc explanation maam...😌😄

@Leah4sci

2 жыл бұрын

Thanks a lot 😊

@shubhammaurya3309

2 жыл бұрын

@@Leah4sci ᴡʟᴄᴍ ᴍᴀᴀᴍ yᴏᴜ ᴅᴇꜱᴇʀᴠᴇ ᴛʜɪꜱ 😄

Medam,please help me, if adjacent carbon of carbocation contain two methyl groups and one phenyl group then which will shift first? Why? And if this carbon contain two phenyl groups and one methyl then which will shift first,why? Which is true order ? Hydride>phenyl>alkyl Or Hydride>alkyl>phenyl?

@Leah4sci

2 жыл бұрын

I'm sorry, but I don't offer tutoring over social media. For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

Why the other C-C bond didn't break in the 2nd step during ring expansion?

@Leah4sci

11 ай бұрын

I'm sorry, but I don't offer tutoring over social media. If you ever find you need help with questions like this again, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

At 3:15 why not shift the carbocation to make way for a six membered group?

@Leah4sci

7 ай бұрын

That is exactly what happens in the next step as I teach just a few minutes later

Nice one...

@Leah4sci

6 ай бұрын

Glad you liked it

Wow! Well appreciated! #2019

@Leah4sci

4 жыл бұрын

Glad I could help!

In one compound 2 times ring expansion is possible or not?????

@Leah4sci

2 жыл бұрын

I'm sorry, but I don't offer tutoring over social media . For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

i love you

@Leah4sci

5 ай бұрын

thanks

awesome

@Leah4sci

7 ай бұрын

Thank you!

but wait....doesn't the ring the strain increase when it changes from a squared shaped to a pentagon?

@Leah4sci

6 жыл бұрын

At which point in the video?

@nicksahloby4097

6 жыл бұрын

ring strain is proportional to the angles in the the cycloalkane. as she mentioned in the video, the carbons are most stable when they form angles around 109.5. going from a square to a pentagon actually reduces the angles at every coroner and thus the strain. it can be a little unclear to think about a square vs. a pentane. instead, picture a cyclopropane, which would be a triangle. now compare that to a square. which one has tighter angles? the triangle. thus more strain.

ring opening

@Leah4sci

6 жыл бұрын

What about it?

errr where the heck do does the h-oh2 come from?

@Leah4sci

10 ай бұрын

If you look on top of and below the reaction arrow, you'll see that the reagents in this reaction are an acid in water. When a strong acid is placed in water, it completely dissociates to form the hydronium ion, which is H3O+. I've rewritten that to H-OH2+, so that you can visualize the proton that is being attacked.

@shadowkxm

10 ай бұрын

ah got it. thank you!!!@@Leah4sci

As am the only one who stumbled upon this on my KZread feed. I know nothing about this subject 😹

@Leah4sci

3 жыл бұрын

Welcome! Glad you found it!

@kevintboy9538

3 жыл бұрын

@@Leah4sci ik it's to much to ask but what's this subject all about and can it be applied to my day life and how

IS 1ST ONE FOLLOWS MARKONIKOVS RULE ??

@Leah4sci

2 жыл бұрын

Markovnikov's rule is for pi bonds

Very good 😊

@Leah4sci

Жыл бұрын

Thanks for watching!