Mechanism of the Apparent Electron-Transfer Reaction between tert-Butoxide Ion and Nitrobenzene

Article abstract of DOI:10.1021/ja00390a015

Potassium tert-butoxide reacts with nitrobenzene in tetrahydrofuran to produce tert-butoxynitrobenzenes.Diring the reaction at least 2 equiv of the potassium salt of nitrobenzene radical anion precipitates per equivalent of substitution products.The reaction is first order in nitrobenzene and second order in tert-butoxide.When a mixture of deuterated and undeuterated nitrobenzene is used, the substitution reaction is selective for the undeuterated reagent.In the presence of molecular oxygen, the nitrobenzene radical anion does not form but the substitution reaction proceeds at the same rate.The isotopic selectivity is undiminshed by the presence of molecular oxygen, demanding that the hydrogen-transfer step occur prior to the electron-transfer steps.These experimental observations demonstrate that substitution occurs by dianion formation followed by electron transfer.