Spontaneous free radical spin adduct formation and 1,3-dipolar molecular addition in reactions of cyanohalocarbons and C-phenyl N-tert-butyl nitrone (PBN)

In this paper, the spin trap C-phenyl N-tert-butyl nitrone double dagger (PEN) is reported to react with cyanohalocarbons (CCl3CN, CHCl2CN, CHBr2CN and CH2BrCN) in a molecular reaction. Some 1:1 molecular adducts are produced in these reactions at room temperature in hexane via 1,3-dipolar cycloaddition. These addition compounds have been studied by GC-MS and MS-MS spectrometry. At the same time, various free radicals;are formed spontaneously from these systems; These radicals are detected by EPR spin trapping techniques and assigned as follows: carbon-centred radical ((CH2CN)-C-. and (CHBrCN)-C-.) spin adducts, nitrogen-centred radical (N-.=C-CCl2, N-.=C=CHCl and N-.=C=CHBr) spin adducts, oxygen-centred radical spin adducts and benzoyl-tert-butylaminoxyl.