Pagodane 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. The ...

with formula whose

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

skeleton was said to resemble a

pagoda A pagoda is an Asian tiered tower with multiple eaves common to Nepal, India, China, Japan, Korea, Myanmar, Vietnam, and other parts of Asia. Most pagodas were built to have a religious function, most often Buddhist but sometimes Taoist, ...

, hence the name. It is 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 ex ...

whose molecule has the ''D''_2''h''

point symmetry group Molecular symmetry in chemistry describes the symmetry present in molecules and the classification of these molecules according to their symmetry. Molecular symmetry is a fundamental concept in chemistry, as it can be used to predict or explain m ...

. The compound is a highly crystalline solid that melts at 243 °C, is barely soluble in most organic solvents and moderately soluble in

benzene Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...

and

chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...

. It sublimes at low pressure. The name pagodane is used more generally for any member of a family of compounds whose molecular skeletons have the same 16-carbon central cage as the basic compound. Each member can be seen as the result of connecting eight atoms of this cage in pairs by four

alkane In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which ...

chains. The general member is denoted 'm''.''n''.''p''.''q''agodane where ''m'', ''n'', ''p'' and ''q'' are the number of carbons of those four chains. The general formula is then where ''s''= ''m''+''n''+''p''+''q''. In particular, the basic compound has those carbons connected by four

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 ...

s (''m''=''n''=''p''=''q''=1), and its name within that family is therefore .1.1.1agodane.

Synthesis and structure

The compound was first synthesized by

Horst Prinzbach Horst Prinzbach (20 July 1931 in Haslach im Kinzigtal – 18 September 2012 in Freiburg im Breisgau) was a German chemist and professor emeritus. Prinzbach studied chemistry at the University of Freiburg and received his PhD under Arthur L� ...

and his associates in 1987, by a 14-step sequence starting from

isodrin Isodrin may refer to either of two chemical compounds: * Isodrin, an organochlorine insecticide which is an isomer of aldrin Aldrin is an organochlorine insecticide that was widely used until the 1990s, when it was banned in most countries. Aldr ...

. In the process they also synthesized .2.1.1agodane and several derivatives. Prinzbach remarked that "the obvious need for he short name 'pagodane'can be readily understood in view of the von Baeyer/

IUPAC The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...

and

Chemical Abstracts CAS (formerly Chemical Abstracts Service) is a division of the American Chemical Society. It is a source of chemical information. CAS is located in Columbus, Ohio, United States. Print periodicals ''Chemical Abstracts'' is a periodical index tha ...

nomenclature", undecacyclo .9.0.0^1,5.0^2,12.0^2,18.0^3,7.0^6,10.0^8,12.0^11,15.0^13,17.0^16,20cosane. In carbon skeleton of pagodane, there can be distinguished many

propellane In organic chemistry, propellane is any member of a class of polycyclic hydrocarbons, whose carbon skeleton consists of three rings of carbon atoms sharing a common carbon–carbon covalent bond. The concept was introduced in 1966 by D. Ginsbu ...

-type fragments. The overall synthesis can be summarized as follows: The scheme depicted here may be shortened to 14 one-pot operations with 24% overall yield. Yet, this variation requires the use of tetrachlorothiophenedioxide instead of tetrachloro-dimethoxycyclopentadiene in two of the early steps. While lesser steps and higher yield look attractive at first sight, this approach had to be given up due to high cost and restricted availability of the dioxide.

Derivatives

Several derivatives are available, such as the

diketone In organic chemistry, a dicarbonyl is a molecule containing two carbonyl () groups. Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls ...

(melting point about 322 °C). Both .1.1.1agodane and .2.1.1agodane form

divalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...

cation An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

s in / . In these cations the electron deficiency is spread over the central

cyclobutane Cyclobutane is a cycloalkane and organic compound with the formula (CH2)4. Cyclobutane is a colourless gas and commercially available as a liquefied gas. Derivatives of cyclobutane are called cyclobutanes. Cyclobutane itself is of no commercial ...

ring. These dications were the first examples to show the phenomenon of

σ-bishomoaromaticity Horst Prinzbach (20 July 1931 in Haslach im Kinzigtal – 18 September 2012 in Freiburg im Breisgau) was a German chemist and professor emeritus. Prinzbach studied chemistry at the University of Freiburg and received his PhD under Arthur L� ...

which was subsequently studied by the Prinzbach group to great length. Pagodane is an isomer of

dodecahedrane Dodecahedrane is a chemical compound, a hydrocarbon with formula , whose carbon atoms are arranged as the vertices (corners) of a regular dodecahedron. Each carbon is bound to three neighbouring carbon atoms and to a hydrogen atom. This compound ...

and can be chemically converted to it.

References

{{reflist, colwidth=30em , refs= Elegant Solutions: Ten Beautiful Experiments in Chemistry Philip Ball RSC 2005 Wolf-Dieter Fessner, Gottfried Sedelmeier, Paul R. Spurr, Grety Rihs, H. Prinzbach (1987), ''"Pagodane": the efficient synthesis of a novel, versatile molecular framework''.

J. Am. Chem. Soc. The ''Journal of the American Chemical Society'' is a weekly peer-reviewed scientific journal that was established in 1879 by the American Chemical Society. The journal has absorbed two other publications in its history, the ''Journal of Analytic ...

, volume 109 issue 15, pp. 4626–42 {{doi, 10.1021/ja00249a029 H. Prinzbach, F. Wahl, A. Weiler, P. Landenberger, J. Woerth, L.T. Scott, M. Gelmont, D. Olevano, F. Sommer, B. von Issendorff: C20 Carbon Clusters: Fullerene - Boat - Sheet Generation, Mass Selection, PE Characterization. Chem. Eur. J. 2006, 12, 6268-6280 , {{doi, 10.1002/chem.200501611 G. K. Surya Prakash (1998), ''Investigations on intriguing long lived carbodications''. Pure & Appl. Chem., volume 70 issue 10, pp. 2001–06
Online version
at iupac.org accessed on 2010-01-14. {{doi, 10.1351/pac199870102001 G.K.S. Prakash, V.V. Krishnamurthy, R. Herges, R. Bau, H. Yuan, G.A Olah, W.-D. Fessner, H. Prinzbach: .1.1.1 and .2.1.1agodane Dications: Frozen Two-Electron Woodward-Hoffmann Transition State Models. J. Am. Chem. Soc. 1988, 110, 7764-7772 Wolf-Dieter Fessner, Bulusu A. R. C. Murty, Horst Prinzbach (1987), ''The Pagodane Route to Dodecahedranes – Thermal, Reductive, and Oxidative Transformations of Pagodanes''

Angewandte Chemie International Edition in English ''Angewandte Chemie'' (, meaning "Applied Chemistry") is a weekly peer-reviewed scientific journal that is published by Wiley-VCH on behalf of the German Chemical Society (Gesellschaft Deutscher Chemiker). Publishing formats include feature-length ...

Volume 26, Issue 5, pp. 451–52 {{doi, 10.1002/anie.198704511 Wolf-Dieter Fessner, Bulusu A. R. C. Murty, Jürgen Wörth, Dieter Hunkler, Hans Fritz, Horst Prinzbach, Wolfgang D. Roth, Paul von Ragué Schleyer, Alan B. McEwen, Wilhelm F. Maier (1987), ''Dodecahedranes from .1.1.1agodanes''.

, Volume 26, Issue 5, pp. 452–54 {{doi, 10.1002/anie.198704521 ''Stable carbocations. Part 267. Pagodane dication, a unique 2.pi.-aromatic cyclobutanoid system'' G. K. Prakash, V. V. Krishnamurthy, Rainer. Herges, Robert. Bau, Hanna. Yuan, George A. Olah, Wolf Dieter. Fessner, and Horst. Prinzbach Journal of the American Chemical Society 1986 108 (4), 836-838 {{doi, 10.1021/ja00264a046 Polycyclic nonaromatic hydrocarbons Cyclobutanes Substances discovered in the 1980s