C12H8S

C12H8S is a molecular formula that denotes compounds composed of 12 carbon atoms, 8 hydrogen atoms, and one sulfur atom. It describes a family of polycyclic aromatic sulfur-containing hydrocarbons in which a single sulfur atom is integrated into a fused ring system. Because multiple isomers share this formula, C12H8S does not identify a unique structure on its own; the exact arrangement of rings determines the specific compound.

The most commonly cited isomer is naphtho[2,1-b]thiophene, a fused bicyclic system in which a thiophene ring is joined to a naphthalene unit. Other isomers arise from different fusion patterns of a thiophene-like fragment within similar polycyclic frameworks. All such compounds are planar and rigid, with aromatic stabilization conferred by their fused rings and the heteroatom sulfur.

Properties of C12H8S isomers are typical of polycyclic aromatic sulfur heterocycles. They are largely nonpolar, exhibit limited water solubility, and dissolve in many organic solvents. Their electronic structures allow for tunable optical and electronic properties, making them of interest in materials science and organic electronics as potential building blocks for dyes, semiconductors, and charge-transport materials.

Synthesis and handling generally involve formation of the polycyclic framework with incorporation of sulfur, using cyclization and rearrangement steps or sulfur-transfer reactions. As with many PAHs and sulfur-containing aromatics, care is taken to minimize exposure due to potential toxicity and environmental concerns associated with polycyclic aromatic compounds.

See also: list of C12H8S isomers; polycyclic aromatic sulfur heterocycles.