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|Section2= |Section3= }} Pagodane is an organic compound with formula whose carbon skeleton was said to resemble a pagoda, hence the name. It is a polycyclic hydrocarbon whose molecule has the ''D''2''h'' point symmetry group. The compound is a highly crystalline solid that melts at 243 °C, is barely soluble in most organic solvents and moderately soluble in benzene and chloroform. 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 chains. The general member is denoted ()pagodane 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 bridges (''m''=''n''=''p''=''q''=1), and its name within that family is therefore ()pagodane.〔 ==Synthesis and structure== The compound was first synthesized by H. Prinzbach et al. in 1987, by a 14-step sequence starting from isodrin.〔 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., volume 109 issue 15, pp. 4626–42 〕 In the process they also synthesized ()pagodane and several derivatives. Prinzbach and co-workers remarked that "the obvious need for (short name 'pagodane' ) can be readily understood in view of the von Baeyer/IUPAC and Chemical Abstracts nomenclature", undecacyclo()icosane.〔 Eight of pagodane's 20 carbon atoms (numbered 3,5,8,10,13,15,18, and 20) have an inverted tetrahedral geometry as in some propellanes – specifically, ()propellane, whose carbon skeleton is a part of pagodane's.〔 The overall synthesis can be summarized as follows: 〔〔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 | 〕 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.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pagodane」の詳細全文を読む スポンサード リンク
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