As mentioned previously, monosaccharides have the ability to react at the –O position in several different ways. In monosaccharide acylation, base promoted conditions can lead to the formation of polyester derivatives.
Play a video:
Was this helpful?
Now let's talk about an oocyte reaction on mono sack rides called mono sack ride Isolation. Alright, guys. So mono sock rides have the ability to react at the opposition or the oxygen position in several different ways. Specifically, when you have a base promoted reaction with acid chlorides or within hydroids, you're able to form polyester derivatives of your glucose. Okay, so here what I've done is I've shown you O a C. Maybe you're a little bit not sure what that is. I'm gonna explain in a second. So it turns out that specifically for this reaction, even though lots of different bases would technically work, Paradyne is a really good choice for reasons that I'm going to show you want to get into the mechanism. Okay? Paradyne is the most commonly used based by far, and it's probably the best choice. And then specifically, even though any a seal group could be added, a Seattle groups are the most common carbon yells there added. Now a Seattle groups are summarized or the condensed structure is always see which I have drawn here. But just remember, what in a Seattle group is guys, It's an O with a carbon eel with a metal group. Okay, so this and then whatever that is attached to this would be an O A C group and always see, would just be, Oh, and then in a so group after that. Okay, I noticed that this is an Esther. That's what we call a polyester driven. Okay, So as before we go through the mechanism, let's just go through the general reaction. So my reaction has once again I'm going to start off with data D glucose, PIRA nose, and I'm gonna react it with a base. That base is going to turn these owes into good nuclear files. And then it can either react with an acid chloride or anhydride to form these polyester derivatives. Now, guys, if you think about it, if you think of what we've learned from the other parts of organic chemistry, it's not a far stretch. Thio. Think about the mechanism that could do this because we know that it's possible for negative charges to come in and do nuclear Felix substitution with good leaving groups. So that's all that's gonna happen here. This is gonna be an n a s nuclear. Feel like a seal substitution mechanism. But don't worry, I'm going to show you that in a second. But I just kind of want to give you a preview that the mechanism is quite easy to think about. All we're gonna do is we're gonna add either this group from the acid chloride or this group, which is the same thing from the anhydride, and we're gonna add that to every single position. So our product in this case would be a fully assimilated glucose pira Knowles. Okay. Also, I just want to make one point. This is not actually called the piranha side because it's not just in our group. It has. It has other oxygen's in it. So it's not called a piranha side. That's on Lee when you specifically have argued in that position. Okay, so anyway, you guys know the general structure. Let's look at the mechanism and see if it makes sense
Play a video:
Was this helpful?
Alright, guys. So here's the mechanism. And what we see is that we're going to start off with our mano sack ride and we're going to react it with what I just drew out as purity. So this is what purity looks like and you might be saying, but Johnny, I mean, I know that parodying is a base. The way that paradigm works, by the way, is that it has a lone pair so that lone pair can come in and d protein ate any of these. Ohh is, in fact, that's gonna do it five times. So what we're gonna get is negatives everywhere. Okay, Now, you might be saying Johnny, but does it specifically have to be parodied? Not necessarily, guys, but parodying is a really good choice, because in general, what you want is a non new Cleo Filic base. Why is that important? Guys, it's important because look at the type of molecule that we're going to use for the second step. In the second step, we're using either an acid chloride or anhydride. Okay, What would happen if I had used o. H in the first step? Could always react with my and hydride hell yeah, it could hide. Relies that to a car. Boxley. Remember back Thio? The three rules of nuclear feel like a seal substitution. The O. H could come in here and kick off the oh, and eventually would get a car. Boxley. So I don't want to use bases that are going to react with my second step, which is why period in is a really good choice. Because pure Dean, it's basic, but it would never actually like attack here. It's not a good enough nuclear fall to do that. So parody is a good choice. Now that I have these negative charges, how can they react with my Aysal groups? Guys, this is just straight up nuclear Filic Aysal substitution where the negative charge could come in. In this case, I'm doing it within anhydride, and they could grab the bottom, kick electrons up to the top. So let's just draw this out for a second, okay? So I'm gonna draw pretty much the whole thing. So now what this is going going to be attached to is oh, and that oh is going to be attached to Let's see Ah, carbon, that has ch three. That has o negative. That has. Oh, and then the rest of this thing here. Okay, so this is the Tetra Hydro Intermediate and all the other oh, groups are preserved so that I would still have Oh, minus Oh, minus Oh, minus. Oh, minus. Okay, So this is my Tetra Hydro Intermediate. And then what's gonna happen is that this negative charge comes down and kicks out this, uh, carbon here or the good leaving group. So what? I'm gonna get it. The end is a molecule. Looks like this. Okay, so I still have all these owes in the same place. But then this one has now oh, attached to let's just do it this way. Attached to a double bond. Oh, and a ch three. And then plus my leaving group, which looks like this. Okay. And if you're confused, How I got that? I just think that this Oh, is this so here this Oh, carbon eel is this guy right here? And this metal group is this one here. So notice that this is what we also call on o a c group, and then this would just happen. Times four. It would happen everywhere else. so that you would get fully assimilated groups in all positions. Cool. So it's not that hard. It's just a variation on what you could do with a basic oxygen. Awesome guys. So we're done with this video. Let's move on to the next.