So like I said, like new projections, there's actually a lot of different types of projections. As you can see, this one right here is called a Fisher projection. It's used mostly for sugar's OK, so later on, if we gettinto sugar chemistry and carbohydrates were using Fisher projections a lot, okay, but they're also used in this chapter as well. Um, to other common ways, that air used our haul worth projection. The hall worth projection is just that three D projection of a ring, that sexual name, and it's usually used for rings. Okay, so it's used to highlight what's at the top and what's at the bottom. And then finally, we have this one called a sawhorse projection, and this one is usually used for stereo chemistry to basically say how these atoms are related to each other in terms of their orientation, their shape, their configuration. Okay, well, in all of these cases, whichever projection we're using also remember that there's Newman is Well, in all these cases, we're gonna have to convert them into bond line before analyzing them completely. Okay, What that means is that these projections they're really good for analyzing certain types of things. But if we want to compare them against other normal molecules, we're gonna have to convert them into bond line first. Because that's really like our czar metric system. That's our standardization, okay?

So basically, you can see I have make a caterpillar. What the hell am I talking about? Well, really. Ah, Fisher projection. Even though it looks two d, it's not really to de the way that it's really supposed to be interpreted is that every vertical bond is going into the page on a wedge. Okay, so these were the vertical and vertical, okay? And then every horizontal bond coming off of it is a wedge. Okay, so those were dashes. I'm sorry. I might have said wedge those air dashes and these were supposed to be wedges. Okay. So even though it looks two D, it's really not to D. That's just the way it's drawn to make it easier. But really, the way that it's supposed to be interpreted is with wedges and dashes. Okay, So what I asked us to do is okay. If we're going to convert this into bond line, we need to use this wedge and dash notation first. So what I say is OK, if you're giving a bond line first, do what I just did and make it wedge and dash like I just did. Then we're gonna use an eyeball and we're gonna pretend like we're looking at it from the side. And what we're going to see is that it's gonna make what I call a caterpillar. Basically, what that means is that this c h o here would be right here. C h o Okay, this C h 20 h would be here ch 20 h. And what we would notice is that we have three different junctions. 123 And these are the places where bonds come off the top. Okay? And if you think about it, maybe draw a line down here. This actually kind of looks like a caterpillar. Right now. This just got really goofy, but it kind of looks like a caterpillar with it's like it's like on a leaf. And it's like eating away. And it's like munching away. And it's got like, it's a little hair sticking up. That's why I call it a caterpillar. Alright, so basically, I don't want you guys don't necessarily draw the whole caterpillar. You don't need to draw face or anything. I'm not gonna be strict about that. But what you should do is realize that this bond here one relates to one right here. So what that means is that I look at the eyeball and I say, Okay, according to the eyeball, what should be in the front and what should be in the back? What is it seeing closest to itself? And what it's saying is that there should be an H in the front because it's the closest one to the eyeball and there should be an O. H in the back, because that's the furthest one from the eyeball on the one carbon. So what I'm referring to here is that I have this h here and then I have this. Ohh here is that making sense? So I'm looking at the one carbon and saying What's in the front? What's in the back? In the same way I would work with the other ones. Then I say to should have an H in the front and in Ohh in the back. And then three should have an O. H in the front and an H in the back. Is that making sense so far? Once I have my caterpillar, then I have to do my last step, and that's going to give me my bond line so we're actually really close to the bond line. The thing is that farmland structures are they ever like that where all the bonds were in a straight line, usually not. Usually there's a zigzag pattern. Right. So we need to restore this back to a zigzag pattern. How do we do that? By rotating every other bond. Okay. And another thing I like to say is that by rotating every even bond Okay, so what we're gonna do here, because I'm gonna show you guys how to do this? Basically, what we do is we have one and two, and what we do is we rotate every other bonds we would rotate to Is my Adam, I'm gonna want to to face down. Okay? And if we rotate to to face down, that's going to restore my zigzag. So now what I'm gonna do is I'm gonna draw this like this. Where I have one is here. Two is here. Three is here and then it goes down like this. So then the C h o isn't the same exact place. The C H 20 H is in the same exact place. Okay. In fact, one in three or in the same exact place. Notice that they were both pointing up before one and three were both pointing up. So that means that the groups that are on one and three should look exactly the same. That means that one should have an O. H at the back, and it means that three should have an O. H at the front. Do I have to draw the ages? No, because this is bond line, remember? In bond line H is air omitted. Okay, so so far, so good. In fact, so far, this is exactly the same molecule. Okay, The only thing that's changed is that now I'm rotating to down. That means that whatever I had on two has to flip. That means that where should the O. H go? Should it go on the back? The front? Where should it go? Since it's rotating, the O. H should now go on the front, Okay, because of the fact that it rotated down, that means that that bond that was in the back is now going to rotate to the front. So now what I've just done is I've just made my bond line. That is a bond line structure right there. Okay. And all I did was I rotated every other bond, So meaning that I rotated this one. This one doesn't get rotated. See, like this one is fine. That one doesn't get rotated. But then this one got rotated, and then this one didn't. Okay, so noticed that every other one I rotate. And if this is a longer chain, then I would have also rotated Adam four to go down so I would have rotated out to Adam four Adam six until my Fisher projection is done. All right? And that would make the exact pattern. All right, So what I want you guys to do is just a free response. Convert the following Fisher projection into a bond line structure. Go ahead and try to solve it yourself, and then I'll go ahead and step in and show us how to do it.

Alright, guys, let's go ahead and go step by step. The first step would be to redraw this with wedge in the dash so I would put this on a dash. I put this on a dash. I would put these guys on wedges br br each h is that cool so far. Now what I want to do is I'm gonna draw my eyeball because that's gonna help me remember what things look like. Okay, Notice that I have carbon one here carbon to hear these air the back of the caterpillar. So now what? I convert this into a caterpillar. What it's gonna look like is like this where I have Adam one Adam to That's the back of the caterpillar. What it's gonna have here is C o H. What is gonna have on over here is ch two and H two. Now I just have to figure out what's on the top. What's on the hairs. Okay, so it should actually be really simple. I should just have for my wedges I should have h and h. Okay, because those are the ones that are closest to the eyeball for the back. What? I should have is br br. Is that making sense so far? Cool. Now I think a question that some of you guys might have is that notice that before appear, I was drawing the h is on the right side and the front, the wedge on the right and the dash on the left. And then here I was drawing the wedge on the left and the dash on the right. It does not matter. You could draw them however you want. As long as the thing that's in the front is still in the front, the things that that's in the back is still in the back. All right, so now we have our caterpillar. So now how do we convert this into bond line? All I do is I rotate every other bond or what? I wanna make sure every other adamis face down every even Adam is face down. So that means it's gonna be Adam to. Okay, so Adam to is going to be the one that has to face down. Okay, so let's go ahead and convert this. What that means is that now this is gonna turn into this this and that, where this is now, Adam one. This is Adam too. Okay, so now I'm gonna actually subtract myself from here, take myself out so that I don't get in the way. So now what should be coming off of one? What should be coming off of one is the same thing as before. I should have the h in the front, but I don't have to draw ages, so I'm just gonna draw the br in the back. Is that cool? So what should be coming off of the one that's on the left of one? The one right here. What should be coming off of there? Well, what I should have there is just the sea 00 h. Just like before. Okay, cool. What should be coming off of the carbon over here? This should be the CH two NT. Okay, so then finally, what should be going right over where my head should be? What should be at the too well, because of the fact that two had to switch down, that means that the BR has to switch its location. So that means that my BR should actually face towards the front. And there you go. That is my bond line structure. Okay, so basically, this is how you make a bond line structure from a cattle from a fissure projection. Notice that you can't just do it in one step. You have to do multiple steps to get here. But if you're consistent, I think you guys will be able to do this just fine.