Intro to Haworth Projections - Video Tutorials & Practice Problems

Intro to Haworth Projections Concept 1

Here, we're going to say that formation of a cyclic acetal produces a new stereo center. My stereo center, we're talking about a chiro center. Now, we're gonna say cyclic acetyl rings can be also viewed from the side. Now, if we take a look here, this is going to be an intra molecular reaction because we have our aldehyde and our alcohol as part of the same structure. We would say here starting from this carbon and carbon. This would be 12345 and six. We would get a six membered ring with oxygen being incorporated within that ring. If we do this, we could get two possibilities where we create our six membered route with oxygen inside because this carbon is our stereo center or chiral center. The oh can orient itself with a wedged bond or a dashed bond. We're gonna say here, groups on the solid wedge point up and groups on the dashed wedge so dashed here point down. Now Hallworth projections, these are just representations of monosaccharide cyclic structures with the ring viewed from the side. If we were to view this first ring from the side. Remember wedged here means it points up. So this is equivalent to or equates to here's our ring, this is a wedge bond. So the oh is pointing up and then here this bond is dashed. So when we look at from the side, the oh will point down. Now, these here are not true Hallworth projections, these are just the base structures that we're looking at to help us kind of understand what's happening at that stereo center. Which direction is that? Oh, pointing? Is it pointing up or is it pointing down later on when we draw the full civic forms of these mono sac rides, there's gonna be more bonds, more groups attached to this ring right now. These are the base forms that we're looking at and eventually they're gonna help us to create the full Hallworth projections. So just keep that in mind creating our cyclic chemic seal is just the first part. Then we're gonna throw in some stereo chem our groups pointing up or pointing down in terms of their connection to the right.

Intro to Haworth Projections Example 1

Here in this example, it says convert the following bond line formula to a Hallworth projection. All right. So here we're going to say that this representation of the ring is the same as here. So all we need to worry about is what kind of bond is connected to the oh groups. If we look here, this is a dashed bond. Remember dash means that it would point down. So we'd show the oh pointing down here. I made it pretty long. So we can see that it's strictly pointing down from that carbon. And then here this bond is wedged, wedged means that it points up. So we show this bond here as up. So this would be the Hallworth projection of our initial molecule. But we're showing which directions are the oh groups pointing dash means that it points down wedged means that it points up.

Convert the following bond-line formula below to a Haworth projection.

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