Hydrocarbons, polycyclic

The next Platonic solid is the cube, and the corresponding polycyclic 

Name Formula Geometry and number of faces (all regular) Face angles Has been prepared  

Incidentally, the regular prisms and the regular antiprisms are also semiregular, i.e., Archimedean, solids. Moreover, the second prism, in its most symmetrical configuration, is a regular solid, the cube and the first antiprism, in its most symmetrical configuration, is also a regular solid, the octahedron. 

Only a few highly symmetrical structures have been mentioned above. The varieties become virtually endless if one reaches beyond the most symmet- 

Dodecahedrane is the one substance of the series with almost ideal geometry, physically the molecule is practically a miniature ball bearing  

---

Dehydrogenation (the conversion of alicycllc or hydroaroraatic compounds into their aromatic counterparts by removal of hydrogen and also, in some cases, of other atoms or groups) finds wide appUcation in the determination of structure of natural products of complex hydroaroraatic structure. Dehydrogenation is employed also for the synthesis of polycyclic hydrocarbons and their derivatives from the readily accessible synthetic hydroaroraatic compounds. A very simple example is the formation of p-raethylnaphthalene from a-tetra-lone (which is itself prepared from benzene—see Section IV,143) ... 

Some information is available about the nitration of polycyclic hydrocarbons and their derivatives, but it is of no quantitative significance. The formation of a cr-complex from anthracene and nitronium ions has been mentioned ( 6.2.3, 6-3)-... 

Cubane (CgHg) is the common name of a polycyclic hydrocarbon that was first synthesized in the early 1960s As its name implies its structure is that of a cube How many rings are pres ent in cubane" ... 

Polycyclic hydrocarbon (Section 3 14) A hydrocarbon in which two carbons are common to two or more nngs... 

Names of polycyclic hydrocarbons with less than the maximum number of noncumulative double bonds are formed from a prefix dihydro-, tetrahydro-, etc., followed by the name of the corresponding unreduced hydrocarbon. The prefix perhydro- signifies full hydrogenation. For example, 1,2-dihy-dronaphthalene is... 

Radicals from Ring Systems. Univalent substituent groups derived from polycyclic hydrocarbons are named by changing the final e of the hydrocarbon name to -yl. The carbon atoms having free valences are given locants as low as possible consistent with the fixed numbering of the... 

Clar, E. "Polycyclic Hydrocarbons", Vol. 1, Academic Press New York,... 

Clar, Polycyclic Hydrocarbons, Academic Press, New York, 1964. 

Singlet oxygen, O2, can readily be generated by irradiating normal triplet oxygen, 2 in the presence of a sensitizer, S, which is usually a fluorescein-type dye, a polycyclic hydrocarbon or other strong absorber of light. A spin-allowed transition then occurs ... 

The most likely substitute for coal is natural gas, which, as noted earlier, releases about 55 percent of the amount of carbon dioxide that coal, on the average, does. In addition, it produces far fewer other pollutants, such as sulfates and polycyclic hydrocarbons, than coal and oil yield on combustion. 

---