Oxidation, Sulfoxidation, and Sulfochlorination

Hydroperoxides can form in fairly long chain reactions with the reaction sequence indicated as follows  

the overall reaction may be written as RH + 02 1 ROOH. The G values for hydroperoxide formation at 50°C range from -16 for 2,2,4-trimethylpentene-l to -400 for cyclohexene (Wagner, 1969). Although this temperature is somewhat lower than the temperature of decomposition of the hydroperoxide, in practice the reactions are conducted at elevated temperatures. In such cases, the radition-induced initiation either eliminates the induction period or allows the recations to proceed at somethat lower temperatutes than would be otherwise required. 

Sulfoxidation has been carried out in paraffins (Black and Baxter, 1958) and in cyclohexane (Hummel et ai, 1964). In sulfoxidation, S02 first adds to a free radical, but the reaction is not complete with the unstable RS04H species. The individual steps of the chain are indicated as follows  

The sulfochlorination chain reaction is not a branching process, but the chain can be very long as the reactions of the indivudual steps indicated in the following are all presumably exothermic  

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