The title compound, 4,9,12,15-tetrathia-tricyclo (5.3.3.3$\sp{2,6}$) hexadecadiene, 12, was prepared by a cesium assisted fourfold cyclization reaction of tetrakis(thiomethyl)ethylene with tetrakis(bromomethyl)ethylene in an ethanol/benzene solvent system. The tetrethiadiene, 12, was prepared in ca. 60% yield, and was the only product observed. In analogous cyclophane fourfold cyclizations two products are observed. A mechanistic study of the fourfold cyclization reaction indicated that ten-membered rings, which can only lead to 12, are formed exclusively in the reaction tetrakis(thiomethyl)ethylene with tetrakis(bromomethyl)ethylene. Alternate routes to prepare another tetrathiadiene were pursued, but were impractical The title compound, 12, was found to be unreactive to many reagents which commonly react readily with olefins. It was found that 12 underwent a facile photocyclization to form the bis-propellane, 29
