Ferrocene is another one of those weird molecules we just stumbled on. Upon reacting the anion of cyclopentadiene with an iron (II) salt, an "unusually stable" compound resulted. In inorganic chemistry, that often means stuff like stable to water or air, since much of this stuff falls apart gleefully.
The image doesn't quite do it justice; ferrocene is actually a "sandwich" of an iron (II) ion and two Cp rings, as you see here. A whole array of "metallocenes" was discovered later, but ferrocene is a classic. Many undergrad chem labs have you synthesize this (or the related, more sensitive nickelocene, for a challenge).
\
All sorts of neat uses have been found for ferrocene, but the real appeal is the shape. Like cubane or other platonic solids, there's something great about a compound that reminds you of a sandwich. Sadly, I don't know of a nickeloferrocene, or anything like that, so we have no nickel and iron sandwiches available to us.
The flaky internet continues. More detailed entries will (hopefully) follow, or more angry phone calls to Charter Cable. Either way, eh?
- Log in to post comments
Mmm, iron sandwich . . . is there a molecule that reminds you of a scandium hamburger?
I never got the chance to do this preparation, but I did get the unenviable experience of having to occupy a corner of a lab with a dicyclopentadiene cracker for a semester, which is incidentally where other students migrated to perform metallocene syntheses. Nothing like the acrid, seemingly girtty aroma of Cp solution hot filtrations to derail ones' train of thought.
It is an undeniably cool structure, however. One of those coordinations that makes it ever so clear that everything you've learned about bonding in the previous 3 years has been a tragically small scratch on the surface of reality.