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For the first time, the asymmetric hydrogenation of quinoxaline-2-carboxylates was performed successfully. The best catalysts are based on iridium complexes modified by chiral phosphorous ligands. Accelerated examination of ligands and catalysts has been undertaken by using a Chemspeed workstation, which enables carrying out, in parallel, eight independent catalytic reactions at the laboratory scale. Tetrahydroquinoxaline-2-carboxylates could be obtained with high yields and up to 74% ee. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuO-ZnO-ZrO 2 catalysts were prepared via continuous coprecipitation in a microfluidic reactor. • High-throughput catalytic tests were carried out on the REALCAT platform. • The optimized catalyst showed a record methanol productivity of 1135 g MeOH kg cat -1 h−1 at 280 °C, 50 bar and 25,000 h−1. • Optimized parameters for the microfluidic catalyst preparation: water as vector fluid, residence time 30 s, low reagents flow rate and precipitation pH = 8. CuO-ZnO-ZrO 2 catalysts were synthetized by controlled continuous coprecipitation in a microfluidic reactor. CuO, ZnO and ZrO 2 contents in catalysts were kept constant at 37.5 wt% of CuO (corresponding to 30% Cu0), 41.0 wt% of ZnO and 21.5 wt% of ZrO 2. Numerous parameters of the continuous microfluidic coprecipitation, such as the nature of the carrier fluid, the residence time in the microfluidic synthesis reactor, the reagents flow rates during the synthesis and the pH, were studied in order to obtain perfectly homogeneous catalytic materials. All catalysts were characterized and then tested in methanol synthesis via CO 2 hydrogenation on the REALCAT platform using high-throughput experiments. The optimum catalytic results were obtained for the catalyst synthesized by the continuous coprecipitation in a microfluidic reactor at following controlled parameters: water as carrier fluid, 30 s of residence time, low total reagent flowrate of 35 µL min−1 and pH equal to 8. This catalyst presented a good CO 2 conversion of 21.4 % along with a methanol selectivity of 33 %, leading to a record methanol productivity of 1135 g MeOH kg cat -1 h−1 at 280 °C, 50 bar and a GHSV of 25,000 h−1 (STP). [ABSTRACT FROM AUTHOR]

New insights into reaction mechanism for catalytic methane combustion are provided in broad operating conditions on Pd/La 0.7 MnO 3 as model natural gas vehicle catalyst. Under lean and dry conditions, a dual mechanism is suggested with active sites combining reactive oxygen species from La 0.7 MnO 3 and palladium instead of single site reaction mechanism. Aging in wet atmosphere has no consequence on the kinetic behavior. On the other hand, in wet atmosphere near the stoichiometry, strong accumulation of hydroxyl groups on the support would suppress the metal-support interface. Accordingly, methane combustion would take place only on Pd particles. [Display omitted] • C-H bond breaking during methane activation assisted by reactive oxygen species from La 0.7 MnO 3. • High stability of Pd-La 0.7 MnO 3 interface upon aging in wet and lean conditions. • Suppression of reactive O species on La 0.7 MnO 3 in the presence of steam due to OH accumulation. • Single Pd sites versus dual sites at Pd-La 0.7 MnO 3 interface governed by the presence of steam. [ABSTRACT FROM AUTHOR]

• Additional elements were introduced into crystalline trigonal Mo 3 VO x catalysts. • Local catalyst structure of the catalysts was strongly influenced the catalytic activity for selective oxidation of ethane, acrolein and allyl alcohol. • Trigonal Mo 3 VO x containing Fe in the crystal structure showed excellent acrylic acid yield by the one pot selective oxidation of allyl alcohol. • Partial location of metals in the micropore affected the catalytic properties. Crystalline "MoVO", "MoVCuO", "MoVFeO" and "MoVWO" catalysts with a trigonal symmetry were successfully synthesized and characterized. The influence of the as-obtained structures on catalytic performances in selective oxidation reactions was investigated. MoVFeO and MoVCuO accomodated Fe and Cu species inside heptagonal channels, while W in MoVWO was incorporated in pentagonal {Mo 6 O 21 }6− units. Whereas MoVO and MoVWO showed catalytic activity in the selective oxidation of ethane and acrolein, MoVFeO and MoVCuO performed very poorly in the same reaction, suggesting that the presence of empty heptagonal channels is related to ethane and acrolein activations. In the selective oxidation of allyl alcohol, substantial amounts of acrolein (formed by oxidative dehydrogenation) and propanal (formed by isomerization) were formed as primary products over MoVO and MoVWO, whereas MoVFeO and MoVCuO preferentially promoted the formation of acrolein. It was found that the local crystal structure around the heptagonal channel was related with a modification of the reaction pathway for the selective oxidation of allyl alcohol. Due to the prevention of isomerization over MoVFeO, a high acrylic acid yield of 83.1% from allyl alcohol was achieved at 350 °C over this sample. [ABSTRACT FROM AUTHOR]