Carbonyl sulphide, photolysis

It is important to understand the sources and loss mechanisms of stratospheric sulfate aerosols. These aerosols are linked to the decrease in ozone at mid-latitudes because they hydrolyse N2O5, reducing the amount of NOx that would otherwise limit the efficiency of chlorine-catalysed ozone depletion. In addition these aerosols scatter light, cooling the planet [127]. Their concentration increases dramatically following major volcanic eruptions however they are always present at background levels. The source of these background aerosols is a matter of debate. In 1976 Paul Crutzen presented the idea that sulfate aerosols result from the photolysis of carbonyl sulphide [128] ... 

The extrusion of sulphur dioxide from a sulphene to give a carbene has been postulated previously, but never authenticated. Flash pyrolysis of a-(toluene-p-sulphonyl)phenyldiazomethane gave i7-tolyl phenyl ketone (15%) and 2-methylfluorene (5%). The former could arise from phenyl-p-tolylsulphene by loss of sulphur monoxide and the latter by loss of sulphur dioxide to give the carbene, which rearranges to the fluorene. Sulphene is postulated as an intermediate in the formation of carbonyl sulphide by the solid-state photolysis of dimethyl sulphone and by various other high-energy processes. 

The Water-gas Shift Reaction.—This reaction is catalysed by M(CO) (activity M = W>Mo>Cr) in the presence of base and under phase-transfer conditions these carbonyls, in common with MS(CO)i2 (M =Ru or Os), are also active in the presence of sodium sulphide. The most active catalysts reported are Fe(CO)6 in basic methanol (turnover No. 2000 per day at 180 °C ) and Rh6(CO)i6 with diamine co-catalysts (e.g., en, turnover No. a 25 h at 100 C). Photolysis of [RuCl(CO)(bipy)a]Cl in water under CO produces COa and catalytically the CO2 is produced in a thermal step, whereas the formation of Ha is photo-initiated. Water-gas has also been used to hydroformylate pent-1-ene in the presence of ruthenium complexes similarly, water-gas is used in reaction (9), which is catalysed by a variety of Group VIII metal complexes... 

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