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Exploratory experiments on effects from a phase transition are reported for a low-melting microcrystalline anthraquinone (N,N,N′,N′-tetraoctyl-2,6-diamino-9,10-anthraquinone or TODAQ). Data for the solid-liquid phase transition are obtained by differential scanning calorimetry and then compared to data obtained by voltammetry. In preliminary electrochemical measurements, microcrystal deposits on a basal plane pyrolytic graphite electrode are shown to undergo a solid-state 2-electron 2-proton reduction in contact to aqueous 0.1 M HClO4 with a midpoint potential Emid,solid = − 0.24 V vs. SCE. The reduction mechanism is proposed to be limited mainly by the triple phase boundary line and some transport of TODAQ molecules towards the electrode surface for both solid and melt. A change in the apparent activation energy for this reduction is observed at 69 °C, leading to an enhanced increase in reduction current with midpoint potential Emid,liquid = − 0.36 V vs. SCE. A change of TODAQ transport along the crystal surface for solid microcrystalline material (for the solid) to diffusion within molten microdroplets (for the liquid) is proposed. Upon cooling, a transition at 60 °C back to a higher apparent activation energy is seen consistent with re-solidification of the molten phase at the electrode surface. Differential scanning calorimetry data for solid TODAQ dry and for TODAQ in contact to aqueous 0.1 M HClO4 confirm these transitions.

Treatment of a range of trisubstituted β,γ-unsaturated esters with 2 equiv of (−)-monoisopinocampheylborane results in hydroboration of their alkene functionalities and reduction of their ester groups to afford chiral 1,3-diols containing two new vicinal β,γ-( anti )-stereocentres in 67–85% enantiomeric excess.

A dynamic acetonitrile | aqueous electrolyte phase boundary in contact with platinised Teflon working electrodes is investigated. High concentrations of salt in the aqueous phase (2 M NaCl and 0.1 M NaClO4) ensure immiscibility and the polar nature of acetonitrile aids the formation of a well-behaved triple phase boundary reaction zone. The one-electron oxidation of tert-butylferrocene in the organic phase without intentionally added electrolyte is studied. The limiting current for the flowing triple phase boundary process is shown to be essentially volume flow rate independent. The process is accompanied by the transfer of perchlorate from the aqueous into the organic phase and the flux of anions is shown to be approximately constant along the dynamic acetonitrile | aqueous electrolyte | platinum line interface. A high rate of conversion (close to 100%) is achieved at slow volume flow rates and at longer platinum electrodes.

Treatment of allylic alcohols containing a 1,1-disubstituted alkene with a palladium catalyst and hydrogen gas (1 bar) results in facile isomerization to their corresponding trisubstituted (E)-allylic alcohols, along with small amounts of the corresponding hydrogenated products.

Mineral oil microdroplets containing the model antioxidant N,N-didodecyl-N′,N′-diethyl-phenylene-diamine (DDPD) are immobilized into a 100×100 pore-array (ca. 10 μm individual pore diameter, 100 μm pitch) in a boron-doped diamond electrode surface. The robust diamond surface allows pore filling, cleaning, and reuse without damage to the electrode surface. The electrode is immersed into aqueous electrolyte media, and voltammetric responses for the oxidation of DDPD are obtained. In order to further improve the current responses, 20 wt% of carbon nanofibers are co-deposited with the oil into the pore array. Voltammetric signals are consistent with the oxidation of DDPD and the associated transfer of perchlorate anions (in aqueous 0.1 M NaClO4) or the transfer of protons (in aqueous 0.1 M HClO4). From the magnitude of the current response, the DDPD content in the mineral oil can be determined down to less than 1 wt% levels. Perhaps surprisingly, the reversible (or midpoint) potential for the DDPD oxidation in mineral oil (when immersed in 0.1 NaClO4) is shown to be concentration-dependent and to shift to more positive potential values for more dilute DDPD in mineral oil solutions. An extraction mechanism and the formation of a separate organic product phase are proposed to explain this behavior.

Treatment of a range of trisubstituted β,γ-unsaturated esters with 2 equiv of (−)-monoisopinocampheylborane results in hydroboration of their alkene functionalities and reduction of their ester groups to afford chiral 1,3-diols containing two new vicinal β,γ-( anti )-stereocentres in 67–85% enantiomeric excess.

Chirality plays a central role in the world around us, with nature and scientists producing an ever-increasing number of chiral molecules that have a wide range of different applications. The word chirality is used as a term to describe a molecule whose enantiomers are non-superimposable on their mirror images. A chiral molecule that contains a single stereogenic center may exist in an enantiopure form or as a mixture of enantiomers in varying ratios. Enantiomers exhibit identical physical and chemical properties when present in an achiral environment; however, they often behave very differently when placed in a chiral environment. Many biologically active molecules such as proteins, nucleic acids, and sugars are chiral biopolymers that are constructed from homochiral building blocks.

Treatment of allylic alcohols containing a 1,1-disubstituted alkene with a palladium catalyst and hydrogen gas (1 bar) results in facile isomerization to their corresponding trisubstituted (E)-allylic alcohols, along with small amounts of the corresponding hydrogenated products.