21. Enolate Chemistry:Reactions at the Alpha-Carbon
Enamine Alkylation and Acylation
21. Enolate Chemistry:Reactions at the Alpha-Carbon
Enamine Alkylation and Acylation - Video Tutorials & Practice Problems
On a tight schedule?
Get a 10 bullets summary of the topic
1
concept
General Reaction
Video duration:
3m
Play a video:
Video transcript
Hey, guys, On this page, we're gonna talk about a reaction called Inamine Calculation and isolation. So, guys, just to catch you up in the key tones and Alba hide section of your textbook, there's a reaction that key tones and Alba hides can undergo with a means that forms in means and enemies. These air functional groups that form from the addition of neutral means to a key toner alga high. Okay, now, specifically, the one that we care about for this page is secondary means because, as you might remember, or maybe you haven't gotten there yet and it's fine or you just forgot. Secondary means are going to react with key tones to specifically give any means. And Inamine has apart a mean at the top and Al Keen at the bottom. Hence the name. Okay, Now, Anna means are really important for us for one reason alone, which is that any means have a nuclear filic Alfa carbon if you think about it, this was the Alfa Carbon to begin with, right? This is still the Alfa Carbon. So any means are able to use that Alfa Carbon to do nuclear feel like attacks. Okay, so enemies have the ability calculate or a slate via the formation of an imminent um, salt. So it essentially happens, guys, is that you have your enemy and you have an electro file. Let's just say that it's an alcohol. Hey, Light to keep it easy. What happens is that the lone pair from the nitrogen can come down to make a double bond. You make that bond you break up on you take this double bond and you attack the alcohol group with it because it's Electra Filic and what you wind up getting is the formation of a nominee, Um, salt really important in many, um, salt, because now that nitrogen has a positive charge. But more importantly, we just calculated the Alfa Carbon. Okay, then we can use dilute acid toe hide relies the in many, um, salt all the way to a key tone. Now, if you're wondering how that happens, this happens through what we call an acid work up. Okay, and there's a very important reaction in organic chemistry to we need to know how to hide relies nitrogen compounds into oxygen containing compounds. There's a multiple step reaction, but if you're interested in looking it up. You can look it up in the I mean, um basically the Indian topic. Okay. When we discuss in means in the carbon eels section keeps on canal, the hides, We're going to talk about the forwards reaction of this, how to go from a key tone toe an Emmy. Okay. And the reverse of that. I mean, reaction is what we call an Indian hydraulic hydraulic sis to get back to the key to Okay, So I'm not gonna go through that whole mechanism because I already have in prior videos. Okay, but just letting you know that we basically use acid to turn an Emmy derivative into a carbon. You okay? But now it's not just a carbon deal. It's Alfa substituted. Okay, So what I want you guys to do is go through these two examples. Try to solve them yourself, do the first one first, obviously. And then I'll solve the first one, and then we'll do the second one together. OK, so go ahead and do the first one
2
example
Predict the Products
Video duration:
2m
Play a video:
Video transcript
Alright, guys. So as you'll notice in this question, it's not asking for a full mechanism. It would take over a page to draw this whole mechanism from scratch. Okay, so we're just gonna predict the products. Like it says. The first thing the first to re agents work together. These we're gonna be an acid catalyzed Inamine reaction. Now, if you're wondering how to draw the product of an enemy mean, I always like to rely on the general formula. So what I would do is I would draw that in Inamine is an end with two bonds at the top. Ah, Bond coming down and then a double bond coming out from one of its sides. Okay, then I just have to determine what is our groups that I substitute for everything. So the end is actually supposed to be attached to a square, so I'm gonna go ahead and complete the square at the top. Okay, Now, the bottom was actually coming from the carbon meal, which was acetone, So it's already drawn perfectly. Okay, Now it's time for the reaction for the actual nuclear Filic attack. So I'm going to draw my alcohol. He lied. I've got a fennel group with a C H two and a br. Okay, so this is gonna be an s and two reaction where I'm gonna take my electrons, move them down, kick out the BR, and what I'm going to get is now an enemy that looks like this drawing a little bit smaller since they don't want to run in a room. Now I'm going to get a carbon that's attached to what? Well, it's attached to now a carbon with a benzene on it. Okay. And a positive charge on that nitrogen. Okay, My last step looks like it just says dilute acid in water. This is the hydraulics step. So after I hydrolyzed with my h 30 plus, which is what that is, I'm going to get my keys home, which looks like this. Interesting, right? So I was able through this reaction. Look what I just did. I started off with acetone, and I added this whole group through my calculation because I went through an Inamine is not so cool. So now we know that we can use any means toe add alcohol groups and a CEO groups to the Alfa position. Okay, awesome. So now that being said this is supposed to be questioned to I don't know why the number isn't there. Go ahead and do question to see if you can get it right. Then I'll show you guys the answer again. Don't draw mechanism. I just want a product.
3
example
Predict the Products
Video duration:
3m
Play a video:
Video transcript
All right, So for this one, I'm definitely gonna draw smaller from the beginning is that we have enough space. So we know that the first two re agents have to do with making my Inamine once again. I'll go back to that general structure oven. Inamine. The general structure is right. It's a nitrogen with bond. Bond. Bond, Double bond. Right. I'd have to plug stuff in. So once I plug stuff in, what that's going to become is I'm really running out of room here. I'll just use the one that I have. Okay, so what I'm gonna get is a method on one side of the end and Ethel on the other side of the end, and then at the bottom, it's gonna be a cyclo hexane. But now it's a cyclo vaccine because it's an enemy. Perfect. Okay, so now I'm gonna introduce that to my calcula Hey, lied, which in this case is really easy. Once a methyl iodide. So this one is going to do an awesome s and two reaction awesome backside attack, and I'm going to attack. And what I'm gonna get is now a new enemy in watching a mini um salt. Right? That looks like this positive. With a metal group there. Okay, Now I'm gonna hide relies in acid. Okay? An acid is going to take me back to my carbon eel. So now I'm just gonna end up with a cyclo hexane own that has a metal group on it. So I was able toe calculate the Alfa position is not so cool. Okay, I keep saying that. You just like Sure, Johnny. Well, guys, let me show you something that is cool that you're gonna like now that I've showed you guys to different reactions and made you think about it, There's a really easy way to predict these reactions. Did you figure it out yet? All it is, guys, is that you just look at your Al Kyohei lied. And whatever your or your electric fall, whatever that electro fall is, you just place it on the Alfa position. Okay? I told you from the beginning, this is just an Alfa substitution. So just take whatever electric failure given and place it there. In the case of the top one, it was a benzel group. That's what I added Here, this is Benzel, right? Has an extra ch two. And the case of the bottom one. It was a metal group. Okay, Now, obviously, if you're professor wants to see, like all the steps involved, draw all of them. But if they just say, predict the products of these four reactions, you honestly don't even need to draw the enemy, right. Because you already know in your head, or I'm gonna make the mean I'm gonna put the thing on the Alfa. I'm going to hide, relies it. So what's the point of even drawing it? You could just draw the product. Notice that this product is just a key tone like it started. Okay, so that I know you like, because that's, like a cheap Okay, Don't use it too much, but just letting you know that's his easiest. This is so now you know pretty much another way to add calculations to Alfa positions. Okay, awesome, guys, Let's move on to the next video.
4
Problem
Problem
Provide the major product after each step for the following reaction.
A
B
C
D
5
Problem
Problem
Which of the following can NOT be formed through the stork enamine reaction with 2-butanone?