Sawhorse to Fischer Projections + Shortcut (vid 3 of 5)

[@vidhivora3578]

Oooommggg...No one on earth could have explained this 3d thing verbally In the way you did..My mind is blown away ❤️❤️❤️

[@Leah4sciMCAT]

Glad you like it!

[@deepikapant4637]

You explain everything so well!!! I wish I had a teacher like you! Thank you soo much for your efforts!! :)

[@Leah4sciMCAT]

You're very welcome!

[@Ramanandtech]

kzbin.info/www/bejne/hX61dK2elsqHqKc

[@رهامالانصاري-ق2ج]

I don't know how to thank you... your explanation was great and you gave me great help... Allah bless you

[@Leah4sciMCAT]

Your kind words are enough!

[@richagole9253]

The absolute best video I got to watch for this stuff! I wasn't able to do this for a lot of time now and this video is so goddamn helpful. Thanks so much, Leah!!!

[@Leah4sciMCAT]

Glad I could help :)

[@fyv0fyv345]

watched maybe 3-4 videos, but this was the most helpful. THANK YOU!

[@Leah4sciMCAT]

Wow, I'm so happy to hear that! Glad I could help!

[@2nh521]

Thanks every time I forget or unknown I watch your videos and get it❤

[@Leah4sciMCAT]

You're so very welcome, I'm happy to help!

[@mrhopesimon7486]

Really love this online lectures.helps a lot..Thanks to contributors

[@Leah4sciMCAT]

You're welcome. Glad you like them

[@quarters7043]

still really helpful in 2018! thanks you so much! now I am confident about the exam tomorrow!

[@Leah4sciMCAT]

Seeing this too late! How did your exam go?

[@quarters7043]

Leah4sciMCAT LOL yea it's kinda too late but the video saved my exam since we had three questions that related to fischer projection. thanks again.

[@Leah4sciMCAT]

I'm glad it could help! I'll keep my fingers crossed for you as you await scores :)

[@amandamusvosvi6638]

You are the reason I understand anything about ochem. Thank you!

[@Leah4sciMCAT]

You're welcome!

[@chisangachanda2000]

I love your tutorials, I'm the hero in organic chemistry, keep up this good work

[@Leah4sciMCAT]

Thank you! Glad you love the videos. :)

[@rachana9070]

Great effort! Thank you so much. Really helped me!

[@Leah4sciMCAT]

You're very welcome

[@nayanjyotinath2055]

Ma'am you are op❤️..... nicely taught

[@Leah4sciMCAT]

Thanks a lot 😊

[@frustrated2520]

Much helpful for students preparing for JEE ... mam plzz try to cover all organic syllabus 😅

[@Leah4sciMCAT]

Like this? leah4sci.com/syllabus

[@parmiduh]

hi, thanks for the video. i cant tell why you decide to specifically rotate one carbon 180 degrees over the other? for example in the last example you provided i got a different projection with F going into the page and Cl sticking out. How can i pick one of the two ?

[@teenachandna2564]

That was very helpful. ThankYou for posting this. My question here is, at 6:30 how do we choose which methyl is to be placed on the top n which on the bottom? And will that make any difference to the molecule?

[@imenehk2048]

I have the same question...

[@Leah4sciMCAT]

There are 2 ways of looking at this molecule. choose one direction then make sure you're consistent throughout

[@BAnirudhSV]

At 2:25, are you referrring to the same molecule by '3d molecule' and 'molecule on the left'?

[@Leah4sciMCAT]

Yes, correct. The 3D molecule is the sawhorse projection on the left of the screen.

[@Skmnsnb]

Thank you sooooooooo much for beautyful explanation.....Organic Chemistry is Beautyful one as like your explanation...Thank You soooooooo much...

[@Leah4sciMCAT]

You are so very welcome!

[@balbhadratubid2084]

Thank you teacher. It was really helpful.🙏🏼🙏🏼🙏🏼

[@Leah4sciMCAT]

You are welcome!

[@NFT-fh5tr]

Thx from France

[@Leah4sciMCAT]

You're welcome

[@hey_farwah]

2023 and still helpful 🎉 thank you

[@Leah4sciMCAT]

So glad to hear this! You're very welcome.

[@bernie9564]

Thank you!!! Still appreciating this !

[@Leah4sciMCAT]

you're welcome!

[@gozdesaglam8551]

omgggg amazing, thanks a lot

[@Leah4sciMCAT]

You're very welcome 😊

[@Addu5221]

Very very helpful. Thanks a lot.

[@Leah4sciMCAT]

+Adnan Kagzi you're welcome

[@Addu5221]

+Leah4sciMCAT Can you also lead us to Geometrical isomerism in cyclic compounds

[@rozhinhosseinishafa1564]

Thanks a lot for this video! it cleared up a lot of concepts, just a question: in the short cut you showed for converting a sawhorse to a fischer, what was the point of dividing the molecule into up and down with a line?

[@Leah4sciMCAT]

You're welcome! The point is that we want both of our non-carbon substituents on either chiral center to ultimately be on the top-side of the molecule. The carbon substituents will need to be on the bottom-side as they are the ones lined up along the backbone of the Fischer projection.

[@thelucidtruth8993]

thank you! this was very helpful for me

[@Leah4sciMCAT]

You're welcome! Glad it helped!

[@jayashreejanakiraman1393]

Thank you sooo much mam . I found it very useful:-)

[@Leah4sciMCAT]

You're very welcome!

[@lbu5543]

Do we look at the fishcer from right or left to convert ot sawhorse? Or does it have to always from left as you did in this video ?? Could you please help!

[@Leah4sciMCAT]

I'm a bit unsure of your question. In the example at 11:00, where I converted the Fischer projection to a Sawhorse, I chose to place the purple carbon on the right and the green carbon on the left. I could have chosen to place those two carbons on opposite sides of the Sawhorse, but it would have changed my perspective on the molecule. Meaning, the atoms in the back would now be drawn in the front, and vice versa. For more help with questions like this, I recommend joining the MCAT Study Hall. For details, visit join.mcatstudyhall.com/ or contact me through my website leah4sci.com/contact/

[@9C_41_PrashastiShrivastava]

2:58 how to decide, which carbon to rotate?

[@Leah4sciMCAT]

When we talk about rotation, we're talking about rotating a carbon to carbon BOND. You could think of it as making the substituents on both carbons face in the same direction. So it's really a matter of perspective. Do you want to draw your Fischer projection by looking at the molecule from below? Then, rotate so that the substituents on both carbons are facing down. Or, do you want to draw your Fischer by looking at the molecule from above? Then, rotate so that the substituents on both carbons are facing up.

[@aerisoraerith]

you saved me. thank you

[@Leah4sciMCAT]

You are welcome!

[@aerisoraerith]

@@Leah4sciMCAT I've watched a lot of your videos, and you always explain so clearly. thank you

[@xyz-ft9cn]

Thank you Leah😊 But I found this after my exam😭

[@Leah4sciMCAT]

I'm sorry you didn't have it in time; fingers crossed the exam turned out ok for you!

[@zuhairreza]

Wow, thanks, Leah!!!!!!! : )

[@Leah4sciMCAT]

You're so welcome!

[@parmanandsingh4760]

very well understood through ur vedio

[@Leah4sciMCAT]

Glad you understood!

[@arbamld2916]

thank you so much ur vedoes are so helpfull but here's a quuestion : does which carbone i choose to put up matter : what if i chose the blue carbone do i have to imagine i'm looking from oposite side (right) so i will see the H from the blue carbon in my left and the bromine on my right

[@Leah4sciMCAT]

+arba mld it's a question of HOW you look at it. The molecule itself will retain its chirality and identity

[@kingo717]

Once you translate everything into fischer does it matter if input my OH at the top left and Br at bottom right? I guess i just see it from another point of view

[@Leah4sciMCAT]

I'm sorry, but I don't offer tutoring through KZbin comments. For help with this and more, I recommend joining the MCAT study hall: join.mcatstudyhall.com/

[@DrReagge]

Hello Leah! I really like your videos, they are great to watch! I have a question and I wonder if you could help me out! The thing is: What if in the Sawhorse-projection, the substitutes don't have an indicator wether they're going in or out of the paper, how do I know which atoms will be "on the side" of the fisher-projection and which will be facing down in it? Help would be much appreciated!

[@Leah4sciMCAT]

+DrReagge If the molecule is achiral then it doesn't matter. If it's chiral but not shown you can draw both enantiomers

[@med_student_gamer1959]

Hey Leah you mentioned in a previous video that the horizontal lines of a Fisher projection represent wedges or molecules going into the page. Yet here, in your first example the hyrdrogens that were on dashes (coming out of the page) ended up on the horizontal lines of the Fisher. So I am a bit confused, do the horizontal lines of a Fisher represent dashes or wedges?

[@studywithanthia]

Abid Karmali wedges

[@Leah4sciMCAT]

To clarify, horizontal refers to wedges coming OUT of the page, and vertical refers to dashes going into the page

[@andreasr.deolinda1095]

at 10:51 cl and h seem to be on the left

[@andreasr.deolinda1095]

im looking at it as if my head was above the purple carbon.. cl is on my left

[@Leah4sciMCAT]

There are many ways to look at a Fischer projection. Please follow along with the video to see and understand how I'm looking at it. Once you get my method use it to craft the method that works best for you

[@muhammad922]

Thanks it's so helpful

[@Leah4sciMCAT]

+‫محمد مصطفى‬‎ you're welcome

[@domenicasilva6368]

Hi, i went to your website and did the quiz but how do we access the answers ? I see a lot of comments of people asking the same thing ?

[@Leah4sciMCAT]

Hello! If you scroll to the bottom of the quiz, there is a red button that says "Send Me The Solutions!". If you click that and put in your email address, I will send you a PDF copy of the quiz solutions. For further questions, feel free to contact me through my website at Leah4sci.com/contact

[@robinmoka4515]

Hi, I'm asked to do Fischer projection from a sawhorse that has no wedge or dash bonds, every bonds is just represented by a straight line, can you help? Thanks

[@Leah4sciMCAT]

The sawhorse projection must be drawn in a way that represents the molecule in three-dimensions. Wedge or dash bonds would be the primary method for showing the necessary conformational information. It’s possible that your sawhorse is drawn so that you are looking down a particular carbon-carbon bond, similar to looking at a Newman projection.

[@Genki_Studios]

Thank you so much!!!

[@Leah4sciMCAT]

You're welcome!

[@thewroman1783]

Thank you soooo sooo soooo much!

[@Leah4sciMCAT]

You're welcome!

[@bunycapy]

valeu professora.. ótima aula

[@Leah4sciMCAT]

Thank you!

[@jaideeppatel8329]

nice teaching concept of projection

[@Leah4sciMCAT]

Glad you enjoyed it!

[@yixidong8364]

why we have to rotate to get fisher projection (you rotate -Br from out of page to inside of page) I dont understand that part

[@Leah4sciMCAT]

+Yixi Dong watch the Fischer intro video which explains the precise orientation requirements

[@trannhathoang296]

i can`t find the video ?

[@jenniferalmeida5627]

thank you for the explanation but that is not a sawhorse projection thats a line diagram projection

[@Leah4sciMCAT]

Thanks for pointing this out

[@cathybiey1575]

hi we need change the br to wedges n h to bold?

[@Leah4sciMCAT]

I'm not following your question. Is this about the video? If so, at what specific point?

[@guillermogiuliana4104]

Thanks so much !

[@Leah4sciMCAT]

You're welcome!

[@boutheinachebouti3454]

a very helpfull exolanation thank you , but like no one have noticed that her voice is similar to celina gomez's ?

[@Leah4sciMCAT]

I'll take that as a compliment! Thanks!

[@MegaKlowie]

I don't understand why when the 180° turn was made the oh and the h stayed the same if you said sad everything turns the opposite way

[@Leah4sciMCAT]

Thanks for asking. I don’t believe I said that everything turns the opposite way. At 2:42, I explained that we need to rotate the bond between the blue and green chiral carbons by 180 degrees, so that the substituents are facing in the same direction. That means keeping the blue end of the molecule in the same position (OH and H stay the same), while rotating the green end of the molecule to face in the same direction as the OH and H.

[@LegendaryWarior]

Thanks A Lot For Clearing My Concepts.

[@Leah4sciMCAT]

You are so welcome.

[@nahidulislam5155]

thank you.

[@Leah4sciMCAT]

You are very welcome!

[@marianneh.1329]

you didn't explain why the OH stays in the same position :(

[@Leah4sciMCAT]

In this particular sawhorse projection, the substituents on the blue carbon (the OH group included) are already sticking up. No further rotation is needed to place it on a Fischer projection where the horizontal lines are, by convention, sticking out of the page. Thanks for watching and asking!

[@brendalim8144]

thank you!

[@Leah4sciMCAT]

+Brenda Lim you're welcome

[@ahmadshah4467]

thanks from pakistan

[@Leah4sciMCAT]

You're welcome

[@EyobAsrat-gx3qz]

Can you help me assignment

[@Leah4sciMCAT]

For tutoring inquiries, email me here: leah4sci.com/contact

[@vaishalisharma2897]

How to convert sawhorse when hydrogen is not in backward

[@Leah4sciMCAT]

I'm sorry, I don't offer tutoring over KZbin comments. For help with this and more, I recommend joining the MCAT study hall. Full details: join.mcatstudyhall.com

[@mdaburaihansk]

❤❤❤❤

[@Leah4sciMCAT]

thank you!

[@massylmallem7820]

I don't think this method works; the chiral centers changed configuration once she converted the molecule into a fisher projection. I thought we were supposed to maintain the configuration.

[@Leah4sciMCAT]

The chiral centers do NOT change R/S configuration when the central carbon-carbon bond in the molecule is rotated. Chiral configuration remains constant using this method for both examples in the video.

[@YounisKhan970v]

Love you mammmm

[@Leah4sciMCAT]

Thanks!

[@lucinaroopal3122]

Excellent

[@Leah4sciMCAT]

thanks so much!

[@dineshranawat449]

very very confusing.. : (

[@Leah4sciMCAT]

+dinesh ranawat sorry you found it confusing. Which aspect did you find confusing?

[@dineshranawat449]

+Leah4sciMCAT nothing Leah ......when I watched this video agin I understood everything...... thank u for helping me.......God bless you... :-)

[@anamlopez729]

Your method is confusing.

[@Leah4sciMCAT]

Sorry to hear that I confused you. What was confusing about it?

[@alexschoengen1362]

Thank you!

[@Leah4sciMCAT]

You're welcome!