Reactivity of nitroso oxides: effect of polar substituents and reaction mechanism

The chemistry of nitroso oxides

“…The ρ value of Hammett's dependence versus the σ constants equals −0.98 (r = 0.977). The ratio of the yields of the corresponding sulfoxides on oxidation of (4-Cl-C 6 H 4 ) 2 S and Ph 2 S by nitroso oxides 54 and 33 is 0.25 106,107 . Thus, nitroso oxides behave as electrophilic oxidants in reaction with sulfides.…”

“…The products of the reaction of nitroso oxides with sulfoxides are the corresponding sulfones and sulfides, that is, both transfer and abstraction of oxygen atom take place 106,107 : The relative rate of the oxygen atom transfer from nitroso oxide 68 to substituted diphenyl sulfoxides was measured to be 1.8 for (4-MeO-C 6 H 4 ) 2 SO, 1.3 for (4-Me-C 6 H 4 ) 2 SO, 1 for Ph 2 SO, and 0.40 for (4-Cl-C 6 H 4 ) 2 SO 106,107 . The ρ value of Hammett's dependence versus the σ constants equals −0.64 (r = 0.984).…”

“…The same trend is observed for the relative rate of the deoxygenation: 1.5 for (4-Me-C 6 H 4 ) 2 SO, 1 for Ph 2 SO, and 0.79 for (4-Cl-C 6 H 4 ) 2 SO. Thus, both reactions are accelerated by ED substituents in a molecule of diphenyl sulfoxide 106,107 .…”

“…The electrophilic oxidation of sulfoxides by nitroso oxides occurs via intermediate formation of the sulfurane oxyradical 94 106 The minor reaction of the deoxygenation of sulfoxides under the photooxidation of aryl azides is a quite interesting process, which may proceed via two possible mechanisms (equations 29 and 30) 106 …”

“…Nitroso compounds. During the photolysis of phenyl azide (0.5 × 10 −2 mol L −1 ) in oxygen-saturated acetonitrile in the presence of nitroso compounds ArNO, the yield of PhNO 2 was reduced dramatically and the formation of ArNO 2 was observed 106 . The addition of 4-chloronitrosobenzene in the concentration of 0.5 and 1 × 10 −2 mol L −1 led to the reduction of the PhNO 2 yield from 34% in the absence of ArNO to 8% and 3%, respectively.…”