On reasonable C, N ratios

Carl Christie of the Edwards Airforce Base is one of my science heroes. My fascination with his work is due to his mastery of highly explosive molecules no one should be making in the right mind (but he does). I also love his fluorophilicity scale to rank Lewis acids, which is something that is both practical and interesting.

Take a look at one of the classics he published a while back together with Olah and Prakash: http://pubs.acs.org/doi/abs/10.1021/ja9714189. This paper talks about the structure of triazidocarbenium ion stabilized by the perchlorate anion… When perchlorate stabilizes an azide-rich ion, you know something special is in the air. What can be better? Perhaps a version of this compound (also made by Carl as I recall) that has azide as the counterion. This is even more exciting. This corresponds to CN12 stoichiometry and is not for sissies, so don’t try this in the comfort of your own fume hood. I recall a story from one of Carl’s former postdocs, Dr. Robert Gnann (who is turning 50 this year, by the way) in which he described violent decomposition of a crystal of one of these derivatives in an oil-filled X-ray capillary. Imagine a nice shiny object slowly descending down the glass tube and touching the bottom…

The exotic molecule mentioned above teaches a lesson that there is a fine line in the nitrogen-to-carbon ratio you do not want to cross. Perhaps CN12 is a bit extreme, though. Tipping the balance in favor of nitrogen is bad and is a well-known issue with organic compounds. As part of the material for my 4th year class, I was wondering if there are natural products that contain scaffolds in which there are more nitrogens than carbons. You might say – who cares? But this is the kind of stuff I like to think about… Interestingly, there is a very peculiar case of fluviol A. A total synthesis of this molecule was reported by Ross Kelly and colleagues in 2006. The synthesis features some awesome hydrazine chemistry, which I am a big fan of. So there you have it: Mother Nature has crossed the “C,N ratio” line too. I am not suggesting fluviol A is explosive, though. Maybe Mother Nature tried even higher ratios in other contexts and the corresponding molecules did not survive (no pun intended) the pressure of evolution. pop


2 thoughts on “On reasonable C, N ratios

  1. Mother nature is known to use diazomethne as a reactive intermediate (when it suits her). Anyway, the excitement in Hell is far more interestin’ than the boredom in Heaven

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