Adsorption of all the reactants and order of addition play a key role in the synthesis of 1,4-diazepines depicting possibility of Langmuir–Hinshelwood mechanism.

This paper describes one-pot solution combustion synthesis of La2–x Sb x O3 (0.02 ≤ x ≤ 0.10). Detailed characterization using X-ray diffraction (XRD) and X- ray photoelecron spectroscopy (XPS) is carried out to understand the doping effect and the oxidation state of antimony. Further, temperature-programmed desorption (TPD) with CO2 is performed for evaluating the basic property and temperature-programmed reduction (TPR) with H2 has been employed to obtain the oxygen storage capacity. The comparative study of La2O3, La2–x Sb x O3 (0.02 ≤ x ≤ 0.10) shows that as the concentration of Sb increases, the basicity decreases and the oxygen storage capacity increases. Thus, nonreducible and basic La2O3 can be transformed to significantly reducible and acidic La2–x Sb x O3 (0.02 ≤ x ≤ 0.10). Further, solid state UV spectroscopy shows that due to the antimony doping, band gap of La2O3 decreases significantly. Moreover, antimony doping also modifies the support property of La2O3 as demonstrated in the catalytic CO2 methanation reaction in the presence of hydrogen. Ru-doped La2O3 and La1.96Sb0.04O3 shows different selectivity toward methane formation and the later favors the reverse water gas shift reaction.

The synthesis of novel and efficient catalysts for acetylene hydrogenation exhibiting high selectivity towards ethylene is important due to the presence of selective acetylene hydrogenation reaction in petrochemical processing. Since adsorption of C gases constitutes the primary step in catalytic hydrogenation and governs the selectivity of the catalysts, we have explored the C-adsorption potential of reducible CeO-based systems. The adsorption of C-gases over CeO-based materials was assessed using experimental in situ spectroscopic techniques and in silico theoretical studies based on density functional theory. The effect of Pd substitution on adsorption was studied. The addition of Pd-ions was found to enhance the adsorption of the gases. Theoretical calculations provided insights into the modes of adsorption, adsorption energetics and reactant-catalyst interactions. The role of the presence of cationic substitution and anionic vacancies in strengthening the adsorption of gases was established. Pd-substituted reduced CeO showed activity for the adsorption of all C gases. On the basis of the aforementioned experimental and theoretical observations, the catalysts were tested for acetylene hydrogenation, and Pd-substituted CeO was found to be a good catalyst for the reaction with complete acetylene conversion observed below 100 °C.

The authors regret that in the original manuscript there were some errors in the structures displayed in Scheme 1 and Table 1. The correct scheme and table are presented herein.Scheme 1 Schematic of a synthetic strategy for preparation of 1,4-benzodiazepine derivatives.