And if a batch gets contaminated, or doesn't come out so clean, well, that might not be so nice, either. The side products from their synthesis, well, those might not be so nice. No, the thing about these compounds is that they can be handled as long as they're very pure and formulated just right. For one thing, I'm a drug discovery chemist, and if you think a structure like this is going to be a drug, then you must be on some strong ones yourself. Stabilized or not, I still won't get near it. Although, as the authors point out, if you heat those crystals up the two components separate out, and you're left with crystals of pure CL-20 soaking in liquid TNT, a situation that will heighten your awareness of the fleeting nature of life. Yes, this is an example of something that becomes less explosive as a one-to-one cocrystal with TNT. There's a recent report of a method to make a more stable form of it, by mixing it with TNT. Not that it's what you'd call a perfect compound in that regard - despite a lot of effort, it's still not quite ready to be hauled around in trucks. Making something like this that can actually be handled and stored is a real accomplishment. No, making things that go off when someone down the hall curses at the coffee machine, that's no problem. What makes it unusual is not that it blows up - go find me a small hexa-N-nitro compound that doesn't - but that it doesn't actually blow up immediately, early, and often. Hexanitrohexaazaisowurtzitane, or CL-20, was developed as a highly energetic, compact, and efficient explosive. That, as it happens, is exactly the case. So that means that someone, somewhere, has perversely made a poly-N-nitro cage compound, as if they'd been dared to cram the most bond energy into the smallest space. I mean, come on, leaving the nitro groups attached to the carbons is for wimps. And since there are six nitrogens and six nitro groups, the first assumption must be that these are all bonded to each other. Nitro groups, as even people who've never taken a chemistry class know, can lead to firey booms, and putting six of them on one molecule can only lead to such. Hexanitro? Say what? I'd call for all the chemists who've ever worked with a hexanitro compound to raise their hands, but that might be assuming too much about the limb-to-chemist ratio. I don't know where those nitrogens are, I think to myself, but I'll bet that's how they got there, because any other pattern would be a synthetic nightmare. You can get some pretty funny-looking structures that way, like hexamethylenetetramine (which I've actually used a couple of times). That's a lot of nitrogens substituted for carbons, and the first thought is that this must be some weirdo condensation product of ammonia, some aldehyde, and who knows what. Moving on out, as you do in a systematic name, I see that this is a hexaaza variation, which makes the picture a bit fuzzier. So the only thing that "isowurtzitane" calls to mind is some complicated framework of fused rings, looking like one of those wire sculptures that unexpectedly fold up flat when you pull on them. I have a vague picture of these "wurtz" compounds being funky three-dimensional cage structures, and that much only from having probably read too many photochemistry papers over the years. But this brings me up short, because very few chemists could walk up to the board and draw an isowurtzitane. You skip to the end in chemical names - Mark Twain would have felt about them the same way he felt about the German language. I'll take you through my own thoughts as an example. We see lots of more complicated nomenclature, of course, but this one some features some speed bumps, that make you go back to make sure that you're reading it correctly. Quite a mouthful, isn't it? Believe me, that one's pretty chewy even for experienced organic chemists.
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