Conversion constants for redox potentials measured versus different reference electrodes in acetonitrile solutions at 25°C

As a result of the adaptation of life to an aerobic environment, nature has evolved a panoply of metalloproteins for oxidative metabolism and protection against reactive oxygen species. Despite the diverse structures and functions of these proteins, they share common mechanistic grounds. An open-shell transition metal like iron or copper is employed to interact with O2 and its derived intermediates such as hydrogen peroxide to afford a variety of metal–oxygen intermediates. These reactive intermediates, including metal-superoxo, -(hydro)peroxo, and high-valent metal–oxo species, are the basis for the various biological functions of O2-utilizing metalloproteins. Collectively, these processes are called oxygen activation. Much of our understanding of the reactivity of these reactive intermediates has come from the study of heme-containing proteins and related metalloporphyrin compounds. These studies not only have deepened our understanding of various functions of heme proteins, such as O2 storage and trans...

Oxygen Activation and Radical Transformations in Heme Proteins and Metalloporphyrins

Free radical functionalization of organic compounds catalyzed by N-hydroxyphthalimide.

Selective alkane transformations via radicals and radical cations: insights into the activation step from experiment and theory.

Copper-Catalyzed sp3 C–H Amination

Absolute rate constants and Arrhenius parameters for hydrogen abstractions (from carbon) by the t-butoxyl radical (tBuO·) are reported for several hydrocarbons and tertiary amines in solution. Comb...

Chemistry of the t-butoxyl radical: evidence that most hydrogen abstractions from carbon are entropy-controlled.

The chlorine atom cage effect was used as a highly sensitive probe for studying the effect of viscosity and the possible role of solvent clusters on cage lifetimes and reactivity for reactions carr...

Free Radical Chlorination of Alkanes in Supercritical Carbon Dioxide: The Chlorine Atom Cage Effect as a Probe for Enhanced Cage Effects in Supercritical Fluid Solvents

Aryl cyclopropyl ketones have frequently been used as probes for single-electron transfer in organic reactions. The implicit assumption in these studies is that upon one-electron reduction, the corresponding arylcyclopropylketyl anions will undergo ring opening in analogy to the cyclopropylcarbinyl free radical. Earlier work in our laboratory has shown that ring opening of arylcyclopropylketyl anions is kinetically and thermodynamically unfavorable when the only substituents on the cyclopropane ring are alkyl or H. This sluggishness is attributable to a loss of resonance energy upon ring opening which is not fully compensated by the reliefofcyclopropane ring strain. Consequently, aryl cyclopropyl ketones are unsuitable probes for single-electron transfer. In this paper, we examine the effect of radical-stabilizing substituents (phenyl and vinyl) on the ring opening of arylcyclopropylketyl anions.

Radical Ion Probes. 3. The Importance of Resonance vs. Strain Energy in the Design of SET Probes Based upon the Cyclopropylcarbinyl-to-Homoallyl Radical Rearrangement

N. Kamrudin Suleman

Papers

Chemistry of the t-butoxyl radical: evidence that most hydrogen abstractions from carbon are entropy-controlled.

Free Radical Chlorination of Alkanes in Supercritical Carbon Dioxide: The Chlorine Atom Cage Effect as a Probe for Enhanced Cage Effects in Supercritical Fluid Solvents

Radical Ion Probes. 3. The Importance of Resonance vs. Strain Energy in the Design of SET Probes Based upon the Cyclopropylcarbinyl-to-Homoallyl Radical Rearrangement

Viscosity-Dependent Behavior of Geminate Caged-Pairs in Supercritical Fluid Solvent

Stereoelectronic effects on chemoselectivity in the free radical bromination of arylcyclopropanes