Electron paramagnetic resonance study of radicals derived from 2- and 3-fluoropropene

Abstract

Using the TiCl3–H2O2, –NH2OH, −Na2S2O8, and −H2O2/Na2SO3, continuous-flow, radical-generating methods at 25 °C, we have successfully characterized by electron paramagnetic resonance spectroscopy radicals formed by the reaction of each of the substrates 2- and 3-fluoropropene with the radicals •OH, •NH3+, •OSO3−, and •SO3−, respectively. With 2-and 3-fluoropropene, respectively, the radicals identified were of general formula CH2(X)ĊFCH3 and CH2(X)ĊHCH2F where -X is the added group, except that treatment of 3-fluoropropene with the TiCl3–H2O2 reaction system also yielded •CH2CH(X)CH2F. The results obtained are discussed in terms of the effect of the presence of the fluorine substituent on both the apparent reactivity of the substrate molecules towards the radical-generating systems and the spectroscopic properties of the radicals observed.