Sulphonyl radicals formation

Sulphonyl phosphates, reactions of 638 Sulphonyl radicals 215 cyclization of 1099 ESR spectra of 1090-1093 formation of 1094-1098 structure of 1090-1094 thermodynamic data for 1094 Sulphonyl sulphenes 196 Sulphonyl sulphoxides alkylation of 311 synthesis of 262... 

Analogous relationships can be expected with phenolic sulphides. The unstable products of transformation are sources of thiyl, sulphinyl, and sulphonyl radicals, which may participate in the formation of sulphonate CXCV and other compounds present in the reaction mixture in very small amounts. It is possible that they are also the cause of formation of species which decompose catalytically tert-BuOOH (cf. also259)). 

Evidence for the formation of alkyl and aryl radicals in some cases following loss of SO2 (Scheme 1) has been obtained. Thus, a small amount of M-pentane was formed in the decomposition of M-pentanesulphonyl azide in mineral oil ). Thermolysis of diphenyl sulphone-2-sulphonyl azide (8) in dodecane at 150 °C gave diphenyl sulphone 9 (27%) and diphenyl sulphone-2-sulphonamide 10 (9%) which arise by hydrogen abstraction by the aryl radical and sulphonyl nitrene, respectively. When this thermolysis was carried out in Freon E-4 at 150 °C, the products were diphenylene sulphone 77 (1.3%) (Pshorr-type cyclization product of the aryl radical) and 10 (1.5%) together with tars 16h Ferro-... 

In 1958, Geiseler and Nagel31 reported the energetics of the chlorosulphonation reaction of n-dodecane (31) with a mixture of S02 and Cl2 (equation 14.) They reported that a mixture of primary and secondary sulphonyl chlorides were formed accompanied by liberation of 39.0 + 0.5 kcal mol-1. The ratio of primary (19) to (the other wise undefined mixture of isomeric) secondary products (32) was determined to be ca 1 11. However, in the absence of further study, we cannot determine how much this reaction is thermodynamically driven (e.g. sulphonyl chloride and free radical stabilities) versus kinetically driven (e.g. free radical reactivities). We will assume that the difference in heats of formation of all of the secondary sulphonyl chlorides are the same. That the difference of the heats of formation of the primary and secondary products is about 2 kcal mol-1 may be derived from values for a set of isomeric primary (n-) and secondary (i-) propyl derivatives shown in Table 8. From the long known and highly accurate heats of formation of liquid n-dodecane (31, — 83.9 kcal mol-1, Reference 3) and of gaseous S02 and HC1 (—70.9 and — 22.1 kcal mol-1, Cl2 equalling 0 by definition, all from Reference 12), we derive the heat of formation of any of the five different secondary n-dodecanesulphonyl chlorides (32) to be —171.9 kcal mol-1 and for the primary n-dodecane-1-sulphonyl chloride (19) a value of —169.9 kcal mol-1. 

Sulphonyl chlorides may be obtained by the reaction of some aliphatic compounds with a mixture of sulphur dioxide and chlorine, under conditions which permit the formation of radicals (equation 139)299,530-533. Usually a mixture of products is formed with amounts of each product being determined by the stabilities of the intermediate alkyl radicals. Thermodynamic or kinetic control of products may be exercized by control of the reaction temperature. 

Sulphuryl halides may be used as reagents in the formation of sulphonyl halides from aromatics, alkenes or alkyl halides. The reaction usually proceeds via a radical mechanism, in the presence of a base (which removes HC1 generated in the reaction). If DMF is used as a solvent, yields are often improved534,535. 

Reaction of polymeric sulphonyl peroxy radicals (PS0200 ) with polymer (PH) leads to the formation of polymeric sulphonyl hydroperoxides (PSO2OOH) ... 

---