Organic Nitrogen and Phosphorous Radicals

Kavun and Buchachenko (247) have found that the primary amino radicals derived from thioamines in the presence of hydroperoxide are very stable and are not readily converted into secondary nitroxide radicals. Kommandeur and Wiersma (107) studied the photodecomposition of tetraphenylhydrazine in rigid solution at 77°K, and the observed ESR spectrum was assigned to the dimer of the diphenyl amino radical (248). Shida et al. (249) have also studied the photodimer of tetraphenylhydrazine and the photochromic dimer of triphenylimidazolyl at low temperature by optical and ESR techniques. These authors noted that photolysis of these compounds induces the homolysis while y-irradiation leads to heterolytic dissociation. Blinder et al. (250) reported the ESR spectrum of the monomer tetraphenylpyrryl radical in 

Recently dialkylamino radicals have been generated by direct photolysis of the corresponding tetrazenes in liquid cyclopropane solution at low temperatures (255)  

Wood and coworkers (141) have observed alkylimino radicals in an adamantane matrix by an interesting photochemical conversion of the aminoalkyl radicals first formed from y-irradiation of alkylamines  

The unsubstituted methylene imino radical, CH2=N, was first observed by Cochran and coworkers (256) by UV-irradiation at 4.2°K of a solid deposit containing 1% HI, 9% HCN, and 9% Ar. This imino radical was also produced recently by direct photolysis of formaldazine (257), an interesting analog of butadiene  

The electronic structures of these imino radicals are particularly interesting as they are ir-radicals as compared to the 6-iminoxy radicals RR C=N-0. Prom the 

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