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  @CookDirWasAbКүн бұрын

  Thank you so much you really helped me understand this!

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  @rojaslabКүн бұрын

  Ayyy! Thanks for watching and I’m so glad to hear that!!

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  @wimptastic228Күн бұрын

  Nice molecule in the Gabriel synthesis

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  @enjoykids6573Күн бұрын

  Thanks for the explanation It's the best and it's helpful to me 👏👏👏

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  @rojaslabКүн бұрын

  That’s so kind! Thank you for watching!

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  @rojaslab5 күн бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @letzte_maahsname7 күн бұрын

  I love the style with the fluorescent markers. Visuals are so underappreciated in teaching. Also your shirt perfectly fits into the color scheme as well :)

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  @rojaslab7 күн бұрын

  Ah, Pascal! That was so kind of you! Vielen Dank für die netten Worte.

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  @maxfrost236012 күн бұрын

  I kinda get that you have time constraints but this is more like an excercise rather than a video for learning the reactions. If i know how sigmatropic rearrangements and diels alder behave under light und heat in regards to orbitals then the rest is pretty much refreshing stuff that i forgot some time ago. Anyway thx for your service

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  @rojaslab11 күн бұрын

  Oh I totally agree! In fact, that was on purpose. I have individual videos that actually do the teaching of each of these topics. This video is to help review. If you’ve ever taken organic chemistry 2, then you know there’s a LOT of reactions to keep track of. This video is meant to help that, not be an introduction to new material!

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  @maxfrost236011 күн бұрын

  Thanks for clarifying! One thing that i‘d like to add is that the formation of the enolate with LDA/NaH is also dependent on the temperature. You can get the thermodynamically favoured product with LDA -78C then heat it at room temp to form the thermodynamic product and subsequently trap it at -78C to react it further. This might be a question on peoples exams.

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  @rojaslab10 күн бұрын

  @@maxfrost2360 You got it, Max! Absolutely crushing it!

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  @bertiebuxton957312 күн бұрын

  i like your channel. you look abit like Seann William Scott. hey i was wondering about your last example phenylacetaldehyde and am abit confused about naming carbons. so in that molecule we can also call it the benzylic carbon?

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  @rojaslab11 күн бұрын

  Haha. I’ve gotten the Stiffler comparison my whole life. Great question! The first carbon adjacent to an aryl ring is always known as the benzylic position, regardless of whether or not there are additional carbons or other functional groups that make up the whole molecule. As long as there is a carbon at that position, chemists call it the benzylic carbon. And thanks so much for your kind words!

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  @tamarabutterworth446112 күн бұрын

  Omg! This is so helpful! I will probably watch this 20 times over the next few weeks 😂

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  @rojaslab12 күн бұрын

  Woohoo! Good luck. You’ve got this! 💪🏾

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  @Oxyten12 күн бұрын

  This video is amazing! As a chemist, I can say there are a lot of things, that chemists should know, compared in one video, and I've never seen videos like that before. Good Job!

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  @rojaslab12 күн бұрын

  This is the nicest comment I’ve ever received! Thank you 🙏🏽 You made my day!

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  @plontetris329712 күн бұрын

  sick vid, coulda really used this last time HAHAHAHA

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  @rojaslab12 күн бұрын

  Lmao. You know, I could have used the same about 10 years ago!

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  @plontetris329712 күн бұрын

  What about azides with PPh3?

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  @rojaslab12 күн бұрын

  Ah yes, the good ol’ Staudinger Reaction. This video was for sophomore level Organic but that’s a great idea for a more advanced video! Thanks for that!

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  @plontetris329712 күн бұрын

  @@rojaslab I see okay thanks HAHA, didn't know I just remembered the reaction had a Wittig-like transition state

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  @rojaslab12 күн бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #InorganicChemistry

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  @rojaslab12 күн бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @benscrafield957512 күн бұрын

  As others have commented, the initial bromination is not the best proposal: you are likely to get a mixture of products, and the most reasonable-looking position for bromination would be the more nucleophilic tertiary C-H, since the Br radical is pretty electrophilic. Also, in the video, you keep referring to this step in terms of Markovnikov’s rule, which describes alkene additions - this chemistry is totally different, and is guided by polarity matching and/or sterics in the HAT step, depending on your H-atom acceptor. It might look like this shouldn’t matter for the route, since you want to eliminate, but the 5-ring creates an issue with exo- vs endo-alkene formation: for 5-rings, exo-alkenes are preferred due to strain. It might be better to start with the bromide or the alkene, for simplicity. The other comment, suggesting that hydroxide would get to the alcohol more quickly, might be correct, but you also risk a lot of side reactions (especially elimination). If you have the bromide, a nicer idea might be to use a Kornblum oxidation to go directly to the ketone. From the alkene, a Tsuji-Wacker would be ideal.

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  @rojaslab12 күн бұрын

  Thanks for the comments! Sounds like you have a lot of experience with organic chemistry!!

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  @keikazazic329614 күн бұрын

  1. Amazing vid 2. mCBPA does not contain at most 6 carbons, but 7

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  @rojaslab14 күн бұрын

  Daaaaang!!!! That’s a great call! So how are we making the epoxide?

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  @keikazazic329614 күн бұрын

  @@rojaslab I only participate in the chemistry Olympiad (at a high level), but epoxide are never taught so idk

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  @rojaslab14 күн бұрын

  @@keikazazic3296 Oh that's really cool. Good luck!!

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  @keikazazic329614 күн бұрын

  Thanks

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  @andrewchyu28923 күн бұрын

  @@rojaslab dmdo possibly, although not commercially available, but very effective. lots of epoxidation agents

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  @tetrasa115 күн бұрын

  mCPBA. Great video btw :)

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  @rojaslab15 күн бұрын

  Haha! You know I tell my students that for whatever reason my brain cannot compute the correct order of letters in that reagent!

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  @mattywadlow212916 күн бұрын

  Won't radical bromine react selectively on the tertiary carbon rather than this secondary carbon you've suggested in this first step? Chlorine may generate a mixture of isomers but i dont think you'll be able to get that isomer from bromine in this fashion.

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  @rojaslab15 күн бұрын

  This is an excellent question that actually has come up by several commenters on this video. The way I understand radical Halogenation is basically that chlorination would lead to a mixture of isomers, as you mentioned. Bromination of Secondary alkyl groups is significantly more likely over primary carbons because the activation energy? At least in propane, is 3 kcal lower, leading to about a 99:1 Secondary bromination. There have been far less studies looking at tertiary radical bromination. In truth, I imagine an actual experiment would yield a variety of products in a mixture. Importantly, the next step is achievable by either position depending on which base you use for the elimination reaction. Either way, your head is in the right place!

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  @HoangHongNgoc18 күн бұрын

  Blackboard and yellow markers would go really well together.

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  @rojaslab18 күн бұрын

  Oh nice! I’ll give it a shot!

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  @Moshito_m23 күн бұрын

  Hoping this will save my butt, LOL.

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  @rojaslab22 күн бұрын

  Lmao! I believe in you!

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  @Dave-oz4rr23 күн бұрын

  What a good content you have ! Too bad I found your channel so late, cheers :)

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  @rojaslab23 күн бұрын

  Thanks, Dave! That means a lot to me!

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  @tamarabutterworth446125 күн бұрын

  This is so helpful! Thanks, Dr. Rojas!

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  @rojaslab25 күн бұрын

  Glad I could help out and thanks for watching!

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  @plontetris329725 күн бұрын

  For the first synthesis, is there a need for the elimination of the alkyl halide? Is it not possible for the alkyl halide to directly undergo nucleophilic substitution in NaOH to form the alcohol?

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  @rojaslab25 күн бұрын

  That’s actually a phenomenal route! Even shorter than mine. Nice work!

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  @rohanganeshan680026 күн бұрын

  Hello! Thank you so much for the video. Just a quick question. For the first problem, when you brominate the starting material in light, isn't it true that the bromination would occur likely towards the tertiary carbon, as radical bromination is considerably more selective than radical chlorination? Regardless, it should still work if the elimination step doesn't utilize a bulky base such as t-BuOK. Just wanted to clarify. Thank you!!

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  @rojaslab26 күн бұрын

  You bring up an excellent point here! You’re also spot on that both pathways allow for the formation of the same alkene depending on base. Here’s how I understand this type of reaction: Radical Chlorination, almost certainly would favor the primary methyl group. Radical bromination typically favors tertiary>secondary>primary. Therefore, at least in my own reasoning, since there are 2 equivalent secondary carbons, the statistical probability would likely favor the secondary carbon, since there are 2 of them and only 1 tertiary carbon. I would wager that a real-life experiment would produce a mixture of products but your line of thinking is perfectly reasonable as well!

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  @rojaslab26 күн бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @emmarentz600728 күн бұрын

  Hello, why wouldn’t the alcohol oxygen at 9:52 not attack the most substituted/tertiary carbon? That was my original guess/intuition, does it have something to do with the benzene ring?

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  @rojaslab28 күн бұрын

  Great question, Emma! Ultimately, the alcohol does nucleophilic attack at the most electrophilic carbon. Since it is the most electromotive position, the electrostatic attractions are strongest there!

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  @chemdelicАй бұрын

  Keep up the good work brother

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  @quinbabaАй бұрын

  I know watching this is going to help me ace my next orgo exam next week :D

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  @rojaslabАй бұрын

  Ayyyy!!! Come report back on how it goes but I have a pretty good feeling you’re going to crush it! 💪🏾

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  @gre7316Ай бұрын

  Hey Rojas, thanks alot for the great content, enjoying your educational work. For this one I was a little confused by your graphic depiction of the mechanism of the claisen condensation in the introduction part at around 1:36 - 2:10 that intermediate is missing a carbon, since if a 2 carbon enolate homolytically condensates with another 2 carbon ester, the intermediate should be a 4 carbon membered species (yours is a 3 Carbon member) or is my brain lagging there?

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  @rojaslab28 күн бұрын

  I'm glad you're thinking about keeping track of the carbons! I can tell you've got this down! If you notice, the starting ester has 2 carbons, 1 at the carbonyl position and 1 as a methyl group. Notably, after the Claisen reaction, you still end up with 4 carbons, 2 at carbonyl positions, and 2 methylene carbons. If you take another look, I think you'll see all 4 carbons present and I appreciate you keeping me honest!

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  @gre731628 күн бұрын

  Hey thanks for the reply :) Im totally with you on the final beta-keto-ester! I was just a bit confused, as I thought, when the enolate attacks the other reactants ester carbonyl position, the intermidiate should have the carbonyl carbon binding to 4 substituents, namely its own methyl group, the negatively charged oxygen, the ester-oxygen and the newly formed carbon-carbon bond from the enolate, but in your intermediate Im missing the methyl group, just talking about the charged di-ester intermidiate structure :) As for further ideas: I work in drug development and I got a lab mate working on his bachelor thesis in route scouting, his first proposed step is claisen condensation with LDA of a 3-Chloro-propionate ester with a butylacetate (i guess its tertbutyl). first he prepares the enolate of the butylacetate and then he adds this mixture via dropping funnel to the chloro-propionate. after acidic workup and chromatography his reaction resulted in a range of products, reaching from elimination products, different beta-keto-esters, as well as starting material. I know its a difficult task, but can you give some general procedure to really stirr the reaction for better yield/purity if you have 2 different esters to start with, as well what is important to avoid or to keep close track of to avoid unwanted side products (e.g. i can imagine that unreacted residual LDA from the enolate preparation will mess up the claisen condensation, as it can react with the other ester to form another enolate... also the enolate can not only act as a nucleophile but also as a base...) is there a way to get rid of unreacted LDA, but keeping the enolate activated before adding the second ester, is there a way to avoid elimination reactions of the chloropropionate? thank you very much :)

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  @abs0lute-zer061Ай бұрын

  One step less for the cyclohexyl bromide to the cyclohexyl methylene bromide would be using the grignard with formaldehyde, aqueous work up, then PBr3

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  @rojaslabАй бұрын

  Ayyyyy!!! That's an awesome route!

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  @rojaslabАй бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @OxytenАй бұрын

  Very good video to generalise this organic reactions

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  @rojaslabАй бұрын

  Thanks, Oxyten! I’m really glad to hear that!

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  @rojaslabАй бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @Nationfirst715Ай бұрын

  Very informative. Keep it up

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  @rojaslabАй бұрын

  Thank you so much! I promise to keep trying!

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  @ryanchin8569Ай бұрын

  ALL the Reactions of Carboxylic Acid Derivatives: Acid Chlorides, Esters, Anhydrides, and more!

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  @saadshayanahmedАй бұрын

  Sir! You're a G.O.A.T Man! Have I never loved Chemistry like this ❤ Easy and simple - no weird talk just to the point 👌🏻

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  @rojaslabАй бұрын

  Wow, thanks! This is the GOATed comment!

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  @rojaslabАй бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @ashleytrack3192Ай бұрын

  how would you tautomerize the last Claisen rearrangement to form an alcohol for the last Practice problem? so, where would that double bond attached to the oxygen go?

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  @rojaslabАй бұрын

  Amazing question! I have a video coming out tomorrow that walks through the mechanism of keto-enol tautomerization. Until then, because of the acidity of α-hydrogens, many carbonyl containing compounds undergo a proton-transfer equilibrium called tautomerism. Tautomers are readily interconverted constitutional isomers, usually distinguished by a different location for an atom or a group. Because tautomers involve the rearrangement of atoms, they are distinctly different than resonance forms, which only differ in the position of bonds and lone pair electrons. This discussion focuses on carbonyl groups with α-hydrogens, which undergo keto-enol tautomerism. Keto implies that the tautomer contains a carbonyl bond while enol implies the presence of a double bond and a hydroxyl group. The keto-enol tautomerization equilibrium is dependent on stabilization factors of both the keto tautomer and the enol tautomer. For simple carbonyl compounds under normal conditions, the equilibrium usually strongly favors the keto tautomer (acetone, for example, is >99.999% keto tautomer). The keto tautomer is preferred because it is usually more stable than the enol tautomer by about 45-60 kJ/mol, which is mainly due to the C=O double bond (-749 kJ/mol) being stronger than the C=C double bond (-611 kJ/mol).

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  @rojaslabАй бұрын

  Here's a free resource showing the rearrangement also: chem.libretexts.org/Bookshelves/Organic_Chemistry/Organic_Chemistry_II_(Morsch_et_al.)/22%3A_Carbonyl_Alpha-Substitution_Reactions/22.01%3A_Keto-Enol_Tautomerism

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  @rojaslabАй бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #InorganicChemistry

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  @alexpawson7282Ай бұрын

  Great video

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  @rojaslabАй бұрын

  Glad you enjoyed it, Alex! You da best!

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  @rojaslabАй бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @colinlusty2812Ай бұрын

  Dr.Rojas is great….i really enjoy his lectures

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  @rojaslabАй бұрын

  You're too kind. Thanks, Colin!

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  @rojaslabАй бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @user-yr2nb4vr3q2 ай бұрын

  Yeah I'll definitely need to adopt the orbital lobes into my diagrams

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  @rojaslab2 ай бұрын

  You’ve got this! 💪🏾

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  @user-yr2nb4vr3q2 ай бұрын

  Lol no I got the grasp of generating the 3d orbital diagrams in maple when at uni, but I'm not entirely sure how worth while that is for molecular interactions, but in the two dimensional the shaded/non shaded lobes seems like it could be handy

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  @rojaslabАй бұрын

  @@user-yr2nb4vr3q haha. Be careful. There are some chemists who would argue that the orbital interactions are the ONLY worthwhile thing to consider!

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  @user-yr2nb4vr3qАй бұрын

  @@rojaslab haha well they are welcome to do so but be perpetually reassured by more and more empirical data if only i knew what I was attempting enrolling for a major in "chemical physics" 😂

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  @user-yr2nb4vr3qАй бұрын

  @@rojaslab but I genuinely believe that should be the only way, sometimes theory results in experimentally determined conclusions and in other times we need to sit there and make theories based on experimentally determined values that are annoying us

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  @rojaslab2 ай бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @BartIwan2 ай бұрын

  Great video! There's a mistake though at 15:33 when you show the product of radical bromation. You added an extra carbon.

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  @rojaslab2 ай бұрын

  Oh geez! You’re totally right. Thanks for the heads up. Please keep me posted if you find anymore so I can let my students know!

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  @rojaslab2 ай бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

• 
  @rojaslab2 ай бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

• 
  @rojaslab2 ай бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry

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  @odins_claw2 ай бұрын

  At 9:40 you said 'insulators' but you meant to say 'semi-conductors'. Great channel. Your teaching style brilliant.

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  @rojaslab2 ай бұрын

  Oh dang, you're absolutely right! Thanks for catching that and your kind words!

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  @rojaslab2 ай бұрын

  If you enjoyed this video, don't forget to give it a thumbs up, subscribe for more educational content, and hit the notification bell to stay updated! Have questions or specific topics you'd like me to cover? Drop them below, and let's keep the chemistry conversation going! #ScienceCommunity #LearningTogether #OrganicChemistry