By taking advantage of the high solubility of CO2 and CH4 at low temperature, we report the electrochemical conversion of these gases in aqueous media down to −40 °C. The 5-fold increase in the concentration of CH4 in gas hydrate slurries makes its electrochemical oxidation feasible at temperatures below the freezing point of water. We also report the electrochemical conversion of CO2 at low temperatures and demonstrate, unexpectedly, that its reduction in these conditions follows an anti-Arrhenius kinetics electrochemical environment. These findings open windows of investigation into electrocatalysis in brines below the freezing point of water.

Nanoparticle metal oxide photocatalysts are attractive because of their increased reactivity and ease of processing into versatile electrode formats; however, their preparation is cumbersome. We report on the rapid bulk synthesis of photocatalytic nanoparticles with homogeneous shape and size via the cathodic corrosion method, a simple electrochemical approach applied for the first time to the versatile preparation of complex metal oxides. Nanoparticles consisting of tungsten oxide (HWO) nanoplates, titanium oxide (TiO) nanowires, and symmetric star-shaped bismuth vanadate (BiVO) were prepared conveniently using tungsten, titanium, and vanadium wires as a starting material. Each of the particles were extremely rapid to produce, taking only 2-3 min to etch 2.5 mm of metal wire into a colloidal dispersion of photoactive materials. All crystalline HWO and BiVO particles and amorphous TiO were photoelectrochemically active toward the water oxidation reaction. Additionally, the BiVO particles showed enhanced photocurrent in the visible region toward the oxidation of a sacrificial sulfite reagent. This synthetic method provides an inexpensive alternative to conventional fabrication techniques and is potentially applicable to a wide variety of metal oxides, making the rapid fabrication of active photocatalysts with controlled crystallinity more efficient.

Iron-catalyzed hydromagnesiation of styrene derivatives using ethylmagnesium bromide has been investigated for the synthesis of benzylic Grignard reagents. The benzylic Grignard reagent formed in the reaction was observed directly and its conformation in solution characterized by multinuclear and variable-temperature NMR spectroscopy. The Grignard reagent could be stored for at least 2 weeks without significant loss in activity. Hydromagnesiation of styrene in tetrahydrofuran gave a mixture of monoalkyl-and dialkylmagnesium species, (1phenylethyl)magnesium bromide (2; RMgBr) and bis(1-phenylethyl)magnesium (3; R 2 Mg), with the equilibrium between these species lying in favor of the dialkylmagnesium species. The thermodynamic parameters of alkyl exchange for the reaction MgBr 2 + R 2 Mg (3) ⇌ 2RMgBr (2) were quantified, with the enthalpy and entropy of formation of 2 from MgBr 2 and 3 calculated as 32 ± 7 and 0.10 ± 0.03 kJ mol −1 , respectively. This methodology was applied, on a 10 mmol scale, as the key step in the synthesis of ibuprofen, using sequential iron-catalyzed alkyl−aryl and aryl−vinyl cross-coupling reactions to give 4isobutylstyrene, which following hydromagnesiation and reaction with CO 2 gave ibuprofen. Each step proceeded in excellent yield, at temperatures between 0 °C and room temperature, at atmospheric pressure. Inexpensive, nontoxic, and air-and moisture-stable iron(III) acetylacetonate was used as the precatalyst in each step in combination with inexpensive amine ligands.

Anion uptake and charge transport in a Polymer of Intrinsic Microporosity (here PIM-EA-TB) is investigated for three cases: (i) the oxidation of ferrocene embedded into a thin film of PIM-EA-TB on a glassy carbon electrode, (ii) the reduction of protons absorbed into a thin film of PIM-EA-TB on a platinum electrode, and (iii) the potential-driven transport of anions and protons in an asymmetrically deposited free-standing PIM-EA-TB membrane working as a current rectifier or "ionic diode". In all three cases the competing effects of the diameter and hydrophobicity (size and hydration energy) of the anion are important. For free-standing membranes very high ionic diode rectification ratios (>10 3 at +/-1 V) are observed in particular for thicker deposits of PIM-EA-TB and for chloride or perchlorate containing electrolyte.

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