In this work, highly efficient Cu x −Mn composite catalysts (0 ≤ x ≤ 0.20) were synthesized by an improved hydrothermal−citrate complex method and tested in the catalytic total oxidation of CO and the removal of NO by CO. The influence of Cu on manganese oxide materials was characterized by several techniques, including FESEM, HRTEM, XRD, BET analysis, H 2 TPR, O 2 TPD, XPS, and DRIFTS. Possible reaction mechanisms for the NO + CO model reaction and CO oxidation were also tentatively proposed. The Cu-modified manganese oxide materials showed higher catalytic activity in CO oxidation and the selective catalytic reduction (SCR) of NO with CO than pure MnO x materials. The improved catalytic activity in CO oxidation observed for the copper−manganese oxide catalyst was associated with a greater amount of adsorbed oxygen species and high lattice oxygen mobility due to the formation of a Cu 1.5 Mn 1.5 O 4 spinel active phase (CuFurthermore, in terms of the CO-SCR model reaction, the surface-dispersed Cu x+ −O 2− −Mn y+ active species could be reduced to a Cu + −□−Mn (4−x)+ active species, which was considered to be the primary active component in the reduction of NO by CO. The results of the catalytic performance testing indicated that Cu 0.075 Mn had the highest catalytic activity in CO oxidation, whereas Cu 0.15 Mn exhibited the best CO-SCR catalytic performance.

Catalytic reduction of NO by CO has been studied over a battery of Cu 3 Ce x Al (1−x) composite oxide catalysts prepared by coprecipitation method. The solids were further characterized by Xray diffraction, laser Raman spectra, N 2 -physisorption (Brunauer−Emmet−Teller (BET)), H 2 -temperature-programmed reduction, inductively coupled plasma atomic emission spectroscopy, X-ray photoelectron spectroscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy techniques. The assessment on the catalytic properties were conducted with the NO + CO model reaction. The influences of Cu and different ratios of Ce and Al on the catalytic performance have been investigated. When the ratio of Ce and Al was 1:4, this sample possessed the best catalytic properties, which was exactly derived from hydrotalcite-like compounds. The introduction of a few cerium species (Cu/Ce = 15:1) in the structure improved the activity/selectivity toward selective catalytic reduction of NO by lowering the temperature of carbon monoxide oxidation.

An enantioselective intermolecular Mannich-type interception of phenolic oxonium ylides with imines has been developed. The cooperative catalysis with achiral dirhodium complex and chiral phosphoric acid has been introduced to circumvent the competitive phenolic O–H bond insertion via dual H-bonding, enabling the synthesis of enantioenriched 2,2-disubstituted dihydrobenzofurans with good to high yield and high to excellent enantioselectivity under mild conditions. Preliminary antitumor activity study of these generated products indicated that the reduction product 7 exhibits high anticancer potency against human lung adenocarcinoma cells (A549 cells, IC50 = 9.13 μM).

No abstract

Superelectrophilic-initiated direct C–H functionalization of thiophenes at the β-position was developed. A series of trans-stereospecific [2,1-a]-IF-thiophene-fused cyclic compounds (4) with saddle-shaped structure were prepared in 17–30% yields through a one-pot superelectrophilic Friedel–Crafts reaction of dihydroindenofluorene with thiophene derivatives. From the crystal packing analyses of 4a, its skeleton shows both strong intermolecular π–π stacking and C–H···π stacking. Furthermore, the ring-dependent photophysical properties of 4 were confirmed by UV–vis absorption and photoluminescence spectroscopy as well as through the study of their fluorescence quantum yield.