As several of my readers had speculated, this year's Chemistry Nobel has gone to Grubbs, Schrock, and Chauvin for the olefin metathesis reaction. So, what the heck is that?

First things first. You're not going to be able to make people think you know about this stuff without a quick hint. It looks as if that word should be pronounced like something from a philosophy course (meta-thesis), but chemists put the accent on the second syllable and almost skip over the third: meh-TA theh-sis. What this reaction does is rearrange carbon-carbon double bonds (alkenes). Like many chemical mechanisms, that's something that happens by itself under harsh conditions, and makes some pretty harsh mixtures of gunk, but doing in a controlled and predictable way is another thing entirely.

This PDF from the Nobel people does a fine job of outlining the chemistry - page 7, in particular, shows the various reactions that you can do. (Here's a less comprehensive HTML look.) Two alkenes can be blended into a new one, which is useful. Many of the applications of the reaction have been with cyclic compounds: if the two alkenes are in the same molecule, the blending reaction forms a new ring. (This Ring-Closing Metathesis process became an instant fad within the organic chemistry community during the mid-1990s, with everyone trying it out to see what it could do.) And you can run the process in reverse - if you have a ring with an alkene in it, the reaction can break it open into two separate ones.

"Big deal", you might say. Actually, it is. Carbon-carbon bonds are the hard currency of organic chemistry. They're tough to handle, but that's what what you have to do to alter the framework of any organic compound. Any clean, predictable way of forming and breaking them is going to be instantly useful. (There still aren't enough reactions that can do that, and if you can find another one, you can go to Stockholm, too). Olefin metathesis is being used all over the place, from polymers to pharmaceuticals. It runs on the benchtop, and in the production plant - it's a good one.

One more thing about this prize: the Nobel committee has done a good job of assigning credit here. Chauvin was the first to work out how a metathesis reaction runs, even though people didn't have a very good way of doing the chemistry. Schrock was the first person to come up with a catalyst that would allow the reaction to run in the real world, but it had some limitations. And Grubbs came up with the catalyst systems that were easy to handle (meaning you could take them out of the bottle in ordinary air!) and worked on a wide range of compounds. This is a fine mix of basic and applied work, and I'm glad the the Nobel recognizes all of it. Congratulations to Yves Chauvin, Richard Schrock, and Robert Grubbs!