As such, DDT is an outstanding pesticide. I have seen it in action with my own eyes. Most impressive. Its use has however been banned in many Western countries for a long time now, because nature does not know what to do with it. It is very chemically stable and very lipophilic, leading to bioaccumulation in the food chain, and in the worst case cancer and death for us humans here at the top of the pyramid.

I know a thing or two about carbon-fluorine bonds as well. They are strong as hell. In fact, they are the strongest of all covalent bonds. As far as I am aware, carbon-fluorine bonds do not occur naturally. Probably for a good reason too. (UPDATE July 19: I was wrong! Check literature reference in the comments below.)

Chemists, and medicinal chemists in particular, love to introduce fluorine here and there. (I only wish I were the exception.) By taking a so-so good compound, we can “fine-tune” (cheesy, I know; we use this term without sarcasm) the properties of the said compound by introducing fluorines in various positions of the structure. We can, among many things, lower the pKa, increase the permeability (especially into the CNS), and toy around with the pharmacokinetics to increase the half-life (our liver enzymes are probably quite unsure how to handle carbon-fluorine bonds) and with the pharmacodynamics to squeeze the compound into the active site and thus make it much more active. Many, many, many marketed drugs now contain carbon-fluorine bonds.

This development is not without a risk. Way up in the atmosphere, simpler flurohydrocarbons (CFCs, Freons et al.) do nasty things to the ozone layer, and down here on Earth… well, we are not really sure yet. Except that once these bonds are created, we know that they will stick around for quite a while.

Back to George Olah. He has been one of my favorite chemists, all categories, for a long time. I mean, how can you not love the creator of the superacid? He is totally worthy of his Nobel Prize. Olah’s magic acid (fluoroantimonic acid) is so strong that it protonates methane (an extraordinary weak base), creating the pentavalent CH5+ ion, an act which violates one or two fundamental concepts of chemistry. Also, how can you not be flabbergasted by an acid that is 2×10^19 stronger than pure sulfuric acid?

The article of today’s ramblings is this: Org. Lett., Article ASAP. (DOI: 10.1021/ol201669a)



Graphical abstract. (Slightly improved by yours truly.)

I fully agree with the opening: “Organofluorine compounds have special properties…”, and some cool, new chemistry is presented throughout the paper (I did not even know fluoralhydrate existed before I read this), and all is fine and dandy until the very last sentence of the concluding remarks: “…fluoroanalogs of DDT, which are potentially biodegradable…”

Hate to say it, but I would be VERY surprised to learn that fluoro-DDT was biodegradable. Does anybody here think compound 4e will be our next, green pesticide? I do not.

P.S. Why not wrap this post up with a limerick that was posted a couple of days ago at Reddit? In other words, I stole it.

A mosquito was heard to complain

That a chemist had poisoned his brain;

The cause of his sorrow

Was paradichloro-

Diphenyltrichloroethane

