CATALYTIC SYNTHESIS OF THIOLANE FROM TETRAHYDROFURAN AND H2S

Tetrahydrofuran recyclization to thiolane (the Yuriev reaction) was st udied in the presence of alumina. Thiolane formation at 200-500-degree s-C was found to be accompanied by cracking of both the initial matter and the product, yielding hydrocarbons and coke deposition on the cat alyst surface. Catalysts of various composition were investigated. Lew is acid sites appeared to play a prominent role in their activity in t he generation of thiolane, i.e., the rate per site increased with the strength of the site. Taking into account kinetic, IR and NMR data, we postulated the reaction mechanism: the interaction between tetrahydro furan and the catalyst yielded an oxo compound, subsequently dissociat ing on Al3+3-O- paired sites. Thiolane formed upon interaction of the intermediate alkoxy complexes and H2S activated on the surface.