Sulfur-bridged polycyclic aromatic compounds

✍ Scribed by H. Akamatu; H. Inokuchi; M. Kinoshita

• Book ID: 102994583
• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 609 KB
• Volume: 21
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(83)90126-4

✦ Synopsis

When polycyclic aromatic hydrocarbons are heattreated with an excess amount of sulfur in evacuated closed tubing, they react with sulfur, liberating hydrogen sulfide; after removing unreacted sulfur, dark-colored compounds in the form of an amorphous solid are obtained. These compounds possess semiconductive properties; the electrical resistivity is greatly reduced from that of the original hydrocarbons. The ESR absorption of these compounds is characterized by the large g-value, which is due to sulfur-centered unpaired electrons.

From these findings, with the results of chemical analysis, we can assume that the polycyclic aromatic nuclei crosslink with each other through the sulfur-bridges, which are good electron transport paths, and yield the aromaticity of the molecule. The sulfur-bridged polycyclic aromatic hydrocarbons can be considered as the structural model of chars and cokes. The ESR studies of a violanthrene-sulfur compound were carried out during its heat-treatment up to 1ClOO"C.