Pyridinic and pyrrolic nitrogen dopants in the N-AC catalyst can adsorb EDC and increase the activity for EDC dehydrochlorination.

Highlights• Ru catalysts deposited inside the channels of CNTs show higher catalytic activity.• Ru-in-CNT catalyst exhibited the acetylene conversion of 95.0 % at 170 °C and 10 h.• CNTs with the inner diameter of 3-7 nm can functionalize as an efficient support.Abstract 1 Ru-based catalysts with different deposition sites were prepared using multiwalled carbon 2 nanotubes as the support and RuCl 3 as the precursor, in order to study the effects of multiwalled 3 carbon nanotubes on the catalytic performance of Ru catalysts for acetylene hydrochlorination. It 4 is suggested that Ru catalysts deposited inside the CNTs channels exhibit the optimal catalytic 5 activity, with the acetylene conversion of 95.0 % and the selectivity to VCM of 99.9 % after 10 h 6 on stream under the conditions of 170 °C and GHSV (C 2 H 2 ) of 90 h -1 . In combination with 7 characterizations of BET, TEM, XRD, TPR, TPD and XPS, it is illustrated that the CNTs with 8 the inner diameter about 3-7 nm can functionalize as an efficient support with unique electron 9 property to enhance the catalytic performance of Ru-based catalysts for acetylene 10 hydrochlorination.11

The catalytic mechanism of Ru-based catalysts in the acetylene hydrochlorination reaction has been investigated via the density functional theory (DFT) method. To study the effect of the chlorine coordination number on the catalytic mechanism, Ru3Cl9, Ru3Cl7, Ru5Cl7, Ru3Cl3 and Ru3 clusters were chosen as the catalytic models. Our results show that the energy barrier for acetylene hydrochlorination on Ru3Cl9 was as high as 1.51 eV at 458 K. When the chlorine coordination number decreased, the energy barriers on Ru3Cl7, Ru5Cl7, Ru3Cl3 and Ru3 were 1.29, 0.89, 1.01 and 1.42 eV, respectively. On Ru3Cl9, the H and Cl atoms of HCl were simultaneously added to C2H2 to form C2H3Cl, while the reaction was divided into two steps on Ru3Cl7, Ru3Cl3 and Ru3 clusters. The first step was the addition of H atom of HCl to C2H2 to form C2H3˙, and the second step was the addition of Cl atom to C2H3˙ to form C2H3Cl. The step involving the addition of Cl was the rate-controlling step during the whole reaction. On Ru5Cl7 cluster, there was an additional step before the steps involving the addition of H and Cl: the transfer of H atom from HCl to Ru atom. This step was the rate-controlling step during the reaction of acetylene hydrochlorination on Ru5Cl7 and its energy barrier was the lowest among all the above-mentioned catalytic models. Therefore, the Ru5Cl7 cluster played the most predominant role in acetylene hydrochlorination with the largest reaction rate constant kTST of 10(3).

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For the first time, an efficient method has been developed by the use of imidazolium ion tethered TsDPENs as efficient ligands for iridium-catalyzed asymmetric transfer hydrogenation (ATH) of α-ketophosphonates in water. The reaction provided the desired product α-hydroxyphosphonates in moderate to good yields (44-78%) and good to excellent enantioselectivities (up to >99% ee) under mild reaction conditions without adding any surfactants. The enantiomeric excess was determined by 13 P NMR by using (-)-cinchonidine as chiral solvating agent, which is a much more convenient method than chiral HPLC.