Radicals tetrazolinyl

Tetrazolin-5-one, l-arylsulfonyl-4-butyl-polymerization, 5, 838 Tetrazolin-5-one, 1-methyl-methylation, 5, 819 Tetrazolin-5-ones 1,4-disubs tituted synthesis, 5, 831 1-substituted alkylation, 5, 794 tautomerism, 5, 794 Tetrazolinyl radicals, 5, 801 1,2,3,4-Tetrazolium-5-aminide nomenclature, 1, 35... 

The disproportionation reaction (Eq. 2) of two tetrazolinyl radicals was studied by Umemoto [18a] and it was concluded that this reaction is a slow process, and therefore this process should also be ruled out as a fast d-step. Importantly, the difference between the redox potentials of cR and R (AEp = 0.25 V) favors the backward reaction. The feasibility of the backward reaction is substantiated by ESR experiments by Maender and Russell [20] who found that the mixture of formazan and tetrazolium salt gave rise to tetrazolinyl radicals. Finally, the solution electron transfer (Eq. 3) is possible as a homogeneous electron transfer (d-step) since it would be reasonable to expect that the redox potentials of the reacting species are very close. However, this reaction would imply dEp/dlogv slope of 19.7 mV (Table 1) which was not observed. Taking all the arguments into account it can be concluded that the mechanism shown in... 

Trisubstituted tetrazolium salts (57) are the oxidation products of formazans. They have been used to produce tetrazolinyl radicals by controlled reduction <73AG(E)455>. 7V-Alkyltetrazolium... 

Soviet workers and others have studied the kinetics of recombination of the arylimidazolyl and arylpyrrolyl radicals formed after homolysis of the dimers and their dependence upon the aryl substitution pattern.517-525 The anodic oxidation of arylpyrroles and arylimidazoles to cation-radicals which may ultimately lose protons to yield the corresponding azolyl radicals has been studied by several groups.450 54,526-529 Tetrazolinyl radicals, e.g., 11, were described several years ago.530-532 They were reviewed in some detail by Neugebauer with their close relatives, the nonaromatic verdazyls. Subsequently, nothing seems to have been reported for this family of radicals. 

The development of the chemistry of the tetrazoles up to the end of 1965 has been reviewed in two papers by Benson.1 2 Shorter reviews of specific aspects of tetrazole chemistry include alkylation reactions of tetrazoles,3 synthesis of tetrazoles from aminoguanidines,4 influence of solvents on tetrazole synthesis from 1,3-cycloadditions of azides,3 general aspects of tetrazole chemistry,6 azidoazomethine tetrazole isomerism,7,8 tetrazolinyl radicals,9 and complexes of 1,5-disubstituted tetrazoles.10... 

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