A staffane or taffane is an

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. T ...

, a polycyclic

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

with molecular structure H- C≡(-CH₂-)₃≡C-sub>''n''-H, for some integer ''n'' ≥ 1. The chemical formula is therefore C_5''n''H_6''n''+2 Staffanes were first obtained in 1988 by P. Kazynski and J. Michl, by spontaneous

polymerization In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many fo ...

of .1.1propellane C₅H₆ or C₂(=CH₂)₃. In the reaction, the axial C-C bond of the propellane (the "bridge") is broken, creating a free bond on each of the two axial

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon mak ...

s (the "bridgeheads"). The resulting structural unit C≡(-CH₂-)₃≡C-is a rigid cage, consisting of two carbon atoms joined by three

methylene bridge In organic chemistry, a methylene bridge, methylene spacer, or methanediyl group is any part of a molecule with formula ; namely, a carbon atom bound to two hydrogen atoms and connected by single bonds to two other distinct atoms in the rest of t ...

s; therefore the joined units are constrained to lie on a straight line. This feature has generated substantial interest among nanotechnology researchers, who have considered staffane oligomers as convenient "rigid rods" for building all sorts of nanostructures. P. Kazynsky, J.Michl (1988), '' taffanes: a molecular-size Tinkertoy construction set for nanotechnology. Preparation of end-functionalized telomers and a polymer of .1.1ropellane''. Journal of the American Chemical Society, volume 110, issue 15, pp. 5225–5226 An oligomer with a specific number ''n'' of units is denoted by 'n''taffane (e.g., taffane, taffane, etc..) The notation taffane is used when the number of units is variable or unspecified; in this case the "n" in the brackets is not a variable, but the letter "n", considered part of the name.

References

Hydrocarbons Polycyclic nonaromatic hydrocarbons {{chem-stub