The present investigation explores the functional features of several novel and other previously ill-defined ferrous and ferric complexes of the picolinic acid anion (Pic), which are used to mediate Gif-type oxidation of hydrocarbons by H 2 O 2 . Complexes [Fe(Pic) 2 (py) 2 ], [Fe(Pic) 3 ]‚0.5py, [Fe 2 O(Pic) 4 (py) 2 ], [Fe 2 (µ-OH) 2 (Pic) 4 ], and FeCl 3 have been employed in oxygenations of adamantane by H 2 O 2 mostly in py/AcOH to reveal that tert-and sec-adamantyl radicals are generated in Gif solutions. The alleged absence of sec-adamantyl radicals from Gif product profiles has been previously interpreted as compelling evidence in support of a non-radical mechanism for the activation of secondary C-H sites in Gif chemistry. The product profile is entirely dictated by trapping of the diffusively free adamantyl radicals, since authentic tert-and sec-adamantyl radicals are shown to partition between dioxygen and protonated pyridine at 4% O 2 (in N 2 ), or between dioxygen and TEMPO at 100% O 2 , in a manner analogous to that observed in Gif oxygenations of adamantane. The low tert/sec selectivity (2.2-4.5) obtained, increasing with increasing dioxygen partial pressure, and the small intramolecular kinetic isotope effect values revealed by employing adamantane-1,3-d 2 (1.06(6) (Ar); 1.73(2) (4% O 2 in N 2 )), indicate the presence of an indiscriminate oxidant under inert atmosphere, coupled to a more selective oxidant at higher partial pressures of dioxygen. Gif oxygenation of DMSO by H 2 O 2 mediated by [Fe(Pic) 2 (py) 2 ] provides pyridine-trapped methyl radicals under argon, as expected for the addition reaction of hydroxyl radicals to DMSO. The reaction is progressively inhibited by increasing amounts of EtOH, generating pyridine-captured CH 3 • CHOH and • CH 2 CH 2 OH radicals. Quantification of the DMSO-versus EtOH-derived alkyl radicals affords an estimate of k EtOH /k DMSO equal to 0.34(3), in reasonable agreement with the kinetics of radiolytically produced hydroxyl radicals (k EtOH /k DMSO ) 0.29). The formation of methyl radicals in Gif oxygenation of DMSO is also supported by the quantitative generation of tert-adamantyl radicals in the presence of 1-iodoadamantane. These results are consistent with the action of hydroxyl radicals in Gif oxygenations by Fe II/III /H 2 O 2 (Ar), most likely coupled to substrate-centered alkoxyl radicals under O 2 . The oxygen-centered radicals perform H-atom abstractions from Gif substrates to generate diffusively free carbon-centered radicals, in accord with previously reported findings.

Torpedo maculopathy is a usually benign condition associated with normal visual acuity and normal visual fields. Our cases demonstrate that torpedo maculopathy may be associated with excavation of the fundus and a corresponding scotoma in the visual field. Visual acuity may be compromised should the excavation encroach upon the central fovea. Knowledge of this previously unreported clinical manifestation of torpedo maculopathy may aid in advancing the understanding of this condition and the care of patients with the disorder.

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