Sulfur atom abstraction reactions sulfide

The principal products in the oxidation of the sulfides are sulfur dioxide and aldehydes. The low-temperature initiating step is similar to reaction (8.138), except that the hydrogen abstraction is from the carbon atom next to the sulfur atom that is,... 

The addition of trisubstituted silanes to carbonyl sulfide has been applied to the synthesis of the corresponding silanethiol derivatives (Reaction 5.40) [78]. In Scheme 5.12 the mechanism is depicted, starting from the silyl radical attack to the sulfur atom of 0=C=S and ejection of carbon monoxide. The resulting silanethiyl radical abstracts hydrogen from the starting silane, to give the silanethiol and to generate fresh silyl radical (see Section 3.4). 

Similarly H2O, H2S may adsorb dissociatively on oxides by proton abstraction and formation of SH groups at room temperature. At higher temperature the replacement of leads to sulfur deposition of with water formation. On NiO(lOO) this last reaction occurs at 570 K and leads to the formation of a surface compound made of an Ni raft with sulfur atoms occupying fourfold hollow sites (Fig. 19) [127,128]. This Ni raft is expanded to fit the Ni(lOO) substrate. For larger exposure the growth of bulk sulfide Ni3S2 proceeds. Interaction of H2S with CoO(lOO) leads to a surface compound similar to that observed on NiO(lOO) but the reaction starts at a lower temperature (373 K). Then the formation of CogSg was observed [129]. 

Kondratiev investigated the photochemical oxidation of carbonyl sulfide from room temperature to 100 °C and found the major products to be CO and SO2. Very little solid product was formed. In his experiments, the OCS was dissociated into CO and S by means of a hydrogen discharge lamp. The atomic sulfur formed in the primary process abstracted another S atom from OCS to form CO and S2. The only role of oxygen in the system was, according to Kondratiev, reaction with the S2 thus formed. The complete mechanism he postulated was... 

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