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An autonomous electrochemical system prototype for ammonia oxidation reaction (AOR) measurements was efficiently done inside a 4'' x 4'' x 8'' 2U Nanoracks module at the International Space Station (ISS). This device, the Ammonia Electrooxidation Lab at the ISS (AELISS), included an autonomous electrochemical system that complied with NASA ISS nondisclosure agreements, power, safety, security, size constrain, and material compatibility established for space missions. The integrated autonomous electrochemical system was tested on-ground and deployed to the International Space Station as a "proof-of-concept" ammonia oxidation reaction testing space device. Here are discussed the results of cyclic voltammetry and chronoamperometry measurements done at the ISS with a commercially available channel flow-cell with eight screen-printed electrodes, including Ag quasi-reference (Ag QRE) and carbon counter electrodes. Pt nanocubes in Carbon Vulcan XC-72R were used as the catalyst for the AOR and 2 μL drop of Pt nanocubes/ Carbon Vulcan XC-72R, 20 wt%, ink was placed on the carbon working electrodes and allowed to dry in air. After the AELISS was prepared for launch to the ISS, a 4 days delayed (2 days in the space vehicle Antares and 2 days space transit to the ISS) cause a slight shift on the Ag QRE potential. Nevertheless, the AOR cyclic voltametric peak was observed in the ISS and showed ca. 70% current density decrease due to the buoyancy effect in agreement with previous microgravity experiments done at the zero-g aircraft. [ABSTRACT FROM AUTHOR]

The synthesis of tetracyclic indole alkaloid (±)-decursivine was accomplished using BINOL-phosphoric acid catalyzed tandem oxidative cyclization as a key step with (bis(trifluoroacetoxy)iodo)benzene (PIFA) as an oxidizing agent. This represents one of the shortest and highest yielding routes for the synthesis of (±)-decursivine from readily available starting materials. [ABSTRACT FROM AUTHOR]

The isomerization of 2-3-dimethyl-1-butene was enhanced over a thousand fold (vs the open circuit value) by spillover protons generated by low currents (electrochemical promotion) on carbon supported Pd catalysts in a polymer electrolyte fuel cell. There was substantial proton spillover catalyzed shift of the double bond of 2-3-dimethyl-1-butene. With 3-3-dimethyl-1-butene, the proton spillover catalyzed methyl shift occurred at low levels and 2-2-dimethyl-butane was the primary product from the simple reduction reaction. Although the substantial non-Faradaic electrochemical modification of catalysis (NEMCA) of the double bond isomerization of an olefin was further demonstrated, the more challenging electrochemical promotion of an olefin methyl shift at the polymer electrolyte Pd/C cathode was less pronounced. [ABSTRACT FROM AUTHOR]