The proposed research concerns the formation of compounds between metals and the elements sulfur, selenium and tellurium, which are members of a group historically known as the chalcogens. This research project has already resulted in the synthesis of a large number of interesting new compounds. Some of the compounds are related to the hydrodesulfurization catalysts which are used for cleaning up petroleum feedstocks, and the research is expected both to lead to a better understanding of the action of these catalysts and to provide knowledge necessary for the design of better catalysts. This proposal concerns synthetic/reactivity studies on molecular complexes containing inorganic chalcogen ligands, i.e. ligands consisting of 1-6 atoms of S, Se or Te. Despite their simplicity (indeed possibly because of it) these ligands are versatile reactivity centers. The project is broken down into three sections. First plans are described making new inorganic chalcogenide anions of Ru, Rh, Nb, Ta, and rare earth/actinide elements. The approach here is to develop new classes of compounds using salt-forming reactions, typified by displacement of carboxylates in tetracarboxylatedimetal compounds by inorganic chalcogen anions. The next section concerns cyclopentadienyl metal sulfides as synthetic intermediates and catalyst models. Particular emphasis is placed on the mechanisms of Cp*2Ru2S4 reactions. Extensions of this work include Cp*2Cr2O4 chemistry, cluster building reactions, and electrophylic M=S functionalities. The closing section focuses on simple metal complexes of thiophenes particularly as they relate to metal sulfide reactivity.
