Cobalt compounds sulfur derivatives

Molybdenum disulfide catalysts, promoted by cobalt or nickel, are used to remove organosulfur compoimds from crude petroleum by hydrogenolysis— hydrodesulfurisation or HDS [124,125,126], These compounds are imdesirable because they poison motor vehicle autoexhaust catalysts and bum to sulfur dioxide, an environmental pollutant. The most difficult compounds to desulfurise are sulfur heterocyclics thiophene, benzothiophene, dibenzothiophene and their methyl substituted derivatives. A typical reaction is the removal of sulfiir from thiophene ... 

Elemental sulfur and some organic sulfur compounds inhibit hydroformylation and hydrogenation catalyzed by cobalt carbonyls (1 2). In order to elucidate the mechanism of this "poisoning" effect, several new, sulfur-containing cobalt carbonyl derivatives have been prepared. 

A particularly important derivative of the [Co(CO)4] anion is the hydrogen derivative, HCo(CO)4. Although this compound is commonly called cobalt carbonyl hydride , the term hydride is actually a misnomer since the hydrogen atom in HCo(CO)4 is not hydridic but strongly protonic in character HCo(CO)4 is as strong an acid as sulfuric acid (9S). Because of its unusual properties and relative simplicity, HCo(CO)4 has been the subject of several spectroscopic (225, 228, 229) and theoretical 230) investigations. 

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