Fischer Esterification

Hey, guys. So now we're gonna talk about one of the more important mechanisms in this course, and that is the mechanism of fisher and stare ification. So Fisher certification is just another name for acid catalyzed a certification. And when you think about what that is, that would just mean that I'm taking a carb oxalic acid. I'm reacting it with alcohol in the presence of acid, and I'm getting and Esther Okay, so I'm getting an Esther product. Hence the term s terrific ation. Now, according to our three rules, this is a totally fine reaction because we said that car looks like acid and Esther's help out the same reactivity. So it's pretty easy to switch between the two. Okay, So according to my three rules, I know this is a favorite reaction. Knows that this can work. So then why do I have this video? Because it turns out that professors just love to ask about this mechanism could kind of one of the fundamental mechanisms of nuclear filic castle substitution. So that's we're gonna go into depth, and we're gonna draw the whole mechanism for this from scratch. So let's go ahead and do that now.

So if you've been following clutch for a while or if you're just naturally good at or go, this shouldn't be so hard because we're going to see these recurring themes of these acid catalyzed reactions that just keep happening over and over with just minor adjustments. Okay, so one thing before begin, I hope you guys air okay with me using a protein ated version of alcohol as my acid because I don't wanna have two different things hanging around. So I'm just gonna let you guys know that alcohol plus h plus my acid is going to give me r O H two plus, which is what I'm gonna use my acid. Okay, so if you couldn't see that, I'll move it up a little bit. Okay? Cool. So I'm gonna say h o r h positive. My first step is gonna be You got it, prote nation. Because it's acid catalyzed, so it's gonna give me something. It looks like this. Ohh ohh. Positive. We know this is gonna open up the opportunity for a resident structure, so let's draw that. Okay, again, guys, if you look in your textbook or if you watch your professor drawing this. They may not include this residence structure, but it's OK because it's still valid. All the arrows, we're going to the same place and just splitting it up a little bit better. Okay on. So now there's a perfect environment for nuclear feel like addition. Right. So I'm gonna take my alcohol. I'm sorry. Nuclear Filic attack. I'm gonna take my alcohol and I'm gonna make this intermediate. What we have we have Ohh! Which o h r and then our our and this has a positive. Okay, so at this point, look what we've done so far, we've done Protein Nation. We have done a nuclear Filic attack. And now what are we gonna dio? Well, guys were trying to get rid of one of the O. H is to replace it with O. R. So we're gonna do a proton transfer so we can get rid of one of those. O h is So this is gonna be proton transfer. After I do that, I get a molecule. Looks like this. Where now I have oh h two positive. Oh, are in our group now, guys, I could do an elimination reaction where the lone pair from my O comes down and kicks out my water But that gives me is now compound that looks like this. And what's my last step? My last step is deep protein nation with the original alcohol to regenerate my catalytic acid. So at the end, I'm gonna get Esther And guess what, guys? This is a completely reversible reaction. So if we wanted to take every step backwards, we could all right makes sense, guys. So I'm not sure if you guys have seen these mechanisms already or not. But if you look at the mechanisms of a settles or if you look at the mechanisms of in means thes are carbon, you'll reactions that air I have videos for in other parts of your clutch. Um, textbook. Right. And if you look at those mechanisms, you're going to see so many similarities. These mechanisms just keep kind of like replicating themselves. Okay, By the way, I forgot to say this was elimination and this was deep protein nation. Awesome. Guys are getting a little better at mechanisms. Hopefully, I hope so. I hope I'm making a little easier for you. So let's move on to the next reaction