187939-76-0Relevant articles and documents
Evidence for divalent iodine (9-I-2) radical intermediates in the thermolysis of (tert-butylperoxy)iodanes. An unusually efficient deiodination of o-iodocumyl alcohols by cyclohexyl radicals
Dolenc, Darko,Plesni?ar, Bo?o
, p. 2628 - 2632 (1997)
1-(tert-Butylperoxy)-3,3-dimethyl-1H-1,2-benziodoxoles (2a and 2b) and 1-(tert-butylperoxy)-3,3-bis(trifluoromethyl)-5-methyl-1H-1,2-benziodo xole (2c) were prepared from chloroiodanes 1a-c and tert-butylhydroperoxide in the presence of potassium tert-butoxide in tetrahydrofuran. Products, kinetic data for the decomposition of 2 in cyclohexane, benzene, toluene, and acetonitrile (E(a) = 31.0 ± 1.0 kcal/mol, log A = 17.0 ± 0.5; 35-70 °C), and the increased rate of decomposition of 2c in benzene-d6 in the presence of a magnetic field (7 T) indicate that homolytic cleavage of the I-O bond in 2 with the formation of iodanyl (9-I-2) and tert-butylperoxyl radicals is the primary decomposition step. The nearly quantitative formation of iodocyclohexane during the decomposition of 2c in cyclohexane is due to the unexpected reaction of cyclohexyl radicals with 2-(2-iodo-5-methylphenyl)-1,1,1,3,3,3-hexafluoro-2-propanol, a primary decomposition product of 2c. The results of a separate study of the deiodination of o-iodocumyl alcohols (3) by cyclohexyl radicals are consistent with an S(H)2 type mechanism.
