Benzene (E 0 = À3.42 V vs. a saturated calomel electrode, SCE [1] ) and its close analogs are among the most challenging organic substrates for reduction. Very few chemical entities have the power to add an electron to ground-state benzene, and these are all derived from highly reactive metals. Thus, the alkali metals sodium (E 0 = À2.71 V) and lithium (E 0 = À3.04 V) dissolve in liquid ammonia to form solvated electrons together with the corresponding metal cations, [2] and similarly calcium (E 0 = À2.89 V) and lithium dissolve in aliphatic amines.[3] These solvated electrons can convert benzene to its radical anion. In the Birch reduction, a protonation step follows for the arene radical anion, but this step is independent of the electron-rich metal. Very recently, a complex derived from samarium(II) iodide, also in the presence of an amine, joined this exclusive set of reagents, in the reduction of the substrate, 4-methoxybenzyl alcohol. [4,5] We now explore whether a completely organic molecule can convert close analogs of benzene to their radical anions, mirroring the behavior of the metals described above. The choice of arene substrate determines the level of the challenge. E 0 values are not routinely available for benzenes, [1] other than those activated by electron-withdrawing groups. However, comparison of the computed lowest unoccupied molecular orbital (LUMO) energies of a range of arenes shows [6] (see Table S1 in the Supporting Information) that benzenes substituted by saturated carbon groups have LUMO energies that lie within 0.2 eV of the value for benzene itself. In contrast, both extended arenes and arenes substituted by electron-withdrawing groups (e.g. CN, CO 2 Me) have much lower LUMO energies and are much easier to reduce. Accordingly, in choosing a discriminating test for a reducing agent, the latter substrates are not appropriate. We have chosen 1,2-diphenylcyclopropanes 4 and 5 and their derivatives 6-11 as the substrates for our study. Both 4 and 5 have LUMO energies within 0.2 eV of that of benzene, are relatively involatile, and can report the intermediacy of radical anions through the opening of the cyclopropane ring (see Scheme 1).Our recent research has probed the ground-state donor properties of highly reactive neutral organic reducing agents. Thus, we have shown that the neutral ground-state organic electron donor 1 [7,8] (Scheme 1) reduces iodoarenes [9,10] to aryl radicals [11] while the stronger donors 2[12] and 3 [13] under milder conditions, afford aryl anions from the same substrates Scheme 1. Reactions of organic electron donors with substrates.