|Figure 1. Snaaaaaakeeeee, a snaaaaaakeeeee!|
Ahh benzene! Europeans fear it, I love the smell of it, and it can look like a snake (Figure 1)! What isn't there to love? Not to mention its qualities as a solvent, and its utility in the azeotropic removal of water from ethanol. But what I'm here to discuss today is how we draw benzene (dude, lets be honest, the Armstrong benzene is fantastic). This came up over coffee a few years ago and I decided to formalize it a little bit. If you want to play along, go ahead and draw a benzene yourself, don't think too hard, but pay attention to how you draw it. Twenty-five graduate student and postdoctoral chemists were surveyed for this blog post and the results were compiled and analyzed for your pleasure (after the jump).
Lets take a look at something simple first: the "aromatic" portion of the benzene. I believe there are three reasonable ways to draw the "middle" of the benzene: 1. with the vertical line to the left, 2. with the vertical line to the right, or 3. with a circle (Figure 2).
Above each molecule, you can see the analysis that arose from our lab: 84% of chemists use the lined notation. I rationalize this overwhelming majority by the fact that this makes mechanisms easier to draw. Its safe to say that if you use the circle notation you are laughed at by your fellow chemists - in fact, one first year graduate student in our lab remarked, "I remember I used to draw a circle, and then I decided to grow up." Although some may say the circle notation is quicker, they are wrong. On top of that it is less aesthetically pleasing to the poster of this blog entry. It is worth noting that users of the circle notation swear by its simplicity and speed.
Things get more complicated when we delve into the "cyclohexane" portion of the molecule (honestly, do the two portions of benzene not have more scientific names, calling it the "cyclohexane" portion is obviously kinda wrong, although you probably get the idea. Steve, help me out here, this is kind of stuff you usually know). For the purposes of this post I have adopted the following notation: the # represents the order in which the bonds are drawn and the arrow represents the direction the bond was drawn (Figure 3).
|Figure 3. Woah dude!|
Right off the bat we have a lot more variability! The "two sides" approach wins out with 20% of the chemists surveyed using this style - starting from the top of the ring and drawing to the bottom, twice. Coming in a close second is the left-side-to-clockwise-to-bottom drawing method at 16%. Lets see what other interesting things we can find out:
- 52% draw the left side first
- 40% start at the top
- 8% draw a single up arrow
- 4% goes in a full circle (thats me! I don't even pick up my pen, so lazy)