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Highlights: [•] Comparison between hydrothermal and microwave synthesis of MOF-74 (Ni, Mg). [•] Microwave synthesis produced MOFs with smaller particle size and larger BET. [•] Comprehensive characterization of all four samples with various analytical methods. [•] Adsorption equilibrium and kinetics of seven small gas molecules at 298K. [•] Calculation of adsorptive separation selectivities for different pairs of gas mixtures. [Copyright &y& Elsevier]

Graphical abstract Highlights • CO 2 -soluble polyethylene glycol diphosphates designed and synthesized elaborately. • Solubility of ligands determined and steric structure affected behavior in scCO 2. • Lanthanides extractions investigated and ligands showed good extraction capability. • Effect of ligand's solubility and steric effect on metal extraction were discussed. Abstract A series of highly CO 2 -soluble open-chain crown ether bridged diphosphates were designed and prepared as chelating ligands which were used to extract lanthanide ions from cellulose paper into supercritical CO 2 (ScCO 2). These ligands were designed by introducing different ester side chains and joining the two phosphorus groups with different length of ethylene oxide group which could provide enhanced solubility and complexation ability. The solubility data of these synthesized diphosophates in ScCO 2 were measured at 313.15 K and 10.65 MPa–13.69 MPa. Lanthanides metal ions including La3+, Ce3+, Pr3+, Nd3+, Sm3+, Gd3+, Er3+, and Yb3+ were successfully removed from the solid matrix by supercritical fluid extractions using these chelating ligands at 313.15 K and 20 MPa. The extraction efficiency of metal ion was affected by chelating ligands' side chain, which increased from 68% to 94% mainly driven by the increased solubility capability. [ABSTRACT FROM AUTHOR]

Herein we present a continuous improvement of visible-light mediated N -dealkylative addition of tertiary amines to dimethyl acetylenedicarboxylates (DMAD) using alkyl halogenides as external oxidants together with base additives. This method is highlighted by excellent tolerance with various tertiary amines and good to excellent yields in short reaction time under mild conditions. [ABSTRACT FROM AUTHOR]

Thiourea-based hydrogen bond donor has been recently disclosed by our group to be an efficient organocatalyst for cross-dehydrogenative coupling (CDC) reactions. Here we present a detailed mechanistic study of this reaction using NMR spectroscopy and kinetic isotope effect experiment. The results revealed that α-amino peroxide is the true intermediate within the catalytic cycle, formed via a thiourea-catalyzed rate-determining hydrogen atom transfer (HAT) process. These experimental investigations not only provide somewhat insight into the mechanism of thiourea-catalyzed CDC reactions but also promote their further applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thiourea itself was used as an organocatalyst for C(sp3) H bond activation. • α-Aminonitriles were obtained in good to excellent yields. • Thiourea acts as a radical initiator instead of non-covalent H-bond donor. Abstract Thiourea itself has been introduced as a mild and efficient organocatalyst for the oxidative α -cyanation of N -aryltetrahydroisoquinolines (THIQs) with trimethylsilyl cyanide (TMSCN), giving the corresponding products in good to excellent yields. Experimental investigations demonstrated that thiourea acts as a radical initiator by abstracting hydroxyl radical (OH) from tert -butyl hydroperoxide (TBHP) directly instead of non-covalent hydrogen bondings (H-bondings) activation. The use of thiourea as a radical initiator offers a new avenue for innovative chemical transformations in organocatalyzed radical chemistry. [ABSTRACT FROM AUTHOR]

[Display omitted] The asymmetric reduction of N -unsubstituted β -enamino esters is the key step for catalytic asymmetric construction of sitagliptin, a prevalent drug for the treatment of type 2 diabetes. However, it is still lack of environment friendly, low-cost, nontoxic, and highly selective catalysts. Herein, we report a series of new silyl ether substituted l -pipecolinic formamides organocatalysts for the asymmetric reduction of N -unsubstituted β -enamino esters with trichlorosilane as the reducing agent. The steric hindrance of silyl ether substitutes can remarkably influence the catalytic performance. The optimized triphenylsilyl substituted catalyst 2k can efficiently catalyze the reduction reaction, affording enantioenriched β -amino ester with excellent yield (95 %) and high ee (82 %). [ABSTRACT FROM AUTHOR]

A simple and readily available cyclopentadiene-based Brønsted acid was employed to catalyze the transfer hydrogenation of 2-substituted quinolines using Hantzsch ester as the hydrogen source. This conceptually new designed organocatalyst demonstrates remarkably high efficiency for this transformation and a variety of substituted 1,2,3,4-tetrahydroquinoline derivatives were afforded in excellent yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

One of the most stable byproducts of biodiesel industry is glycerol, for which there’s lack of a large-scale application currently. Thermal plasma treatment is a potentially viable means of recycling glycerol by converting it into syngas. In this work, a rotating DC arc plasma reactor was used to decompose glycerol in order to produce syngas. The effect of plasma input power, glycerol feed rate, and water content in feedstock on the syngas conversion was investigated. It was found that the product gas stream, on an argon-free basis, contained 38% CO and 56% H 2 , with the balance being methane, ethylene, and little C4 hydrocarbons. Complete carbon conversion and energy conversion efficiency of 66% could be obtained with sufficient input power. Water content of feedstock influenced the amount of CO and H 2 in the product gas. Magnetic flux intensity of the reactor showed negligible effect on the composition of the product gas, carbon conversion and energy conversion efficiency, but could prevent the anode and plasma reactor from severe erosion. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fractional extraction was proposed to separate long chain unsaturated fatty acids. [•] COSMO-RS was used for fast extractant screening and separation mechanism analysis. [•] High separation selectivity was obtained by liquid–liquid extraction equilibrium. [•] Mixed extractant was proposed to separate LCUFAs and to eliminate emulsification. [ABSTRACT FROM AUTHOR]

Abstract: The solution of ionic liquid (IL) bmimCl and polar organic solvent formamide (FA) were used to form nonaqueous microemulsions in cyclohexane by the aid of surfactant Triton X-100 (TX-100). The phase behavior of the bmimCl–FA/TX-100/cyclohexane system at 25±0.1°C was studied. Electrical conductivity measurement was used to identify the microstructures of the nonaqueous microemulsions. Based on the phase diagram, the reverse microemulsions containing bmimCl–FA as the internal phase were investigated by the dynamic light scattering (DLS) and UV–vis spectroscopy. The result of DLS experiments confirmed the formation of reverse microemulsions of bmimCl–FA in cyclohexane. The UV–vis studies with methyl orange (MO) and methylene blue (MB) as absorption probes further confirmed the existence of reverse microemulsions. UV–vis studies using CoCl2 as probe also indicated that the reverse microemulsions could dissolve metal salt. [Copyright &y& Elsevier]

Abstract: The effect of ionic liquids (ILs) on temperature-induced percolation of water/sodium bis-(2-ethylhexyl) sulfosuccinate (AOT)/isooctane microemulsions was investigated. Several properties of microemulsions, including percolation temperature threshold (T p), viscosity, and droplet size were used to demonstrate the effect of the structure of ILs on percolation phenomena. Percolation phenomena of microemulsions were clearly observed after the addition of IL, and the T p of microemulsions increased with increases in the ILs concentration. In addition, T p was greatly affected by the alkyl side-chain length of imidazolium cation and increased with increases in chain length. However, T p was slightly affected by the ILs anions due to the charge exclusion caused by the head group of surfactant. Additionally, the viscosity and droplet size of microemulsions decreased with the addition of ILs, and the observed decrease correlated roughly with an increase in T p. These results also confirm the influence of ILs on percolation phenomena of the microemulsions. [Copyright &y& Elsevier]

• Visible-light induced direct amidation of benzoylformic acids with tertiary amines. • Direct synthesis of a series of α-ketoamide derivatives under mild condition. • The photocatalytic system can be applied to a variety of benzoylformic acids. A visible-light induced direct amidation of benzoylformic acids with tertiary amines has been explored. Tertiary amines underwent N -dealkylative amidation with α-keto acid in the presence of [Ir{dFCF 3 ppy} 2 (bpy)]PF 6 and Cs 2 CO 3 , affording the corresponding α-ketoamides in good yields under mild conditions. This transformation exhibits a wide substrate scope and provides a facile synthetic approach to α-ketoamides. [ABSTRACT FROM AUTHOR]