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Spiroaxillarone A, a novel and unique spirocyclic dinaphthalene natural product with significant antimalarial activity, was regioselectively synthesized from tetrahydrocurcumin in five steps with an overall 10% yield. Key features of the synthesis involved an oxidized free radical cycloaddition to build the spiro ring central skeleton and an oxidized dehydrogenation to introduce two double bonds via enol silicon ether from diketones.

A core-shell structure zirconium silicate encapsulated carbon (C@ZrSiO4) pigment was synthesized by a molten-salt assisted method. The experimental results indicated that the Na2WO4 molten-salt associated with the synthesis of ZrSiO4 at low temperature and controlled the morphology of the encapsulation pigment simultaneously. The encapsulated pigment prepared with the assistance of Na2WO4 molten-salt showed regular microcubes about 3.0 μm, while the pigment in the absence of molten-salt have serious aggregation with a particle size of 12.78 μm. Moreover, the maximum addition amount of carbon black was increased significantly from 15 wt% to 40 wt% after adding molten-salt, while the chromatic value L* of C@ZrSiO4 pigment decreased from 68.21 to 33.08 accordingly. The pigment exhibited excellent thermal stability at high temperature, making it a promising candidate for ceramic decoration.

The combination of photoredox catalysis and enamine catalysis has enabled the development of an enantioselective aerobic oxidative cross-dehydrogenative coupling between glycine derivatives and simple ketones or aldehydes, which provides an efficient approach for the rapid synthesis of enantiopure unnatural α-alkyl α-amino acid derivatives in good yield with excellent diastereo- (up to >99 : 1) and enantioselectivities (up to 97% ee). This process includes the direct photoinduced oxidation of glycine derivatives to an imine intermediate, followed by the asymmetric Mannich-type reaction with an enamine intermediate generated in situ from a ketone or aldehyde and a chiral secondary amine organocatalyst. This mild method allows the direct formation of a C–C bond with simultaneous installation of two new stereocenters without wasteful removal of functional groups., A visible-light-induced enantioselective aerobic oxidative cross-dehydrogenative coupling between glycine derivatives and simple ketones or aldehydes is achieved.

The nominal enantiomer of chlorabietol B was regio- and stereoselectively synthesized from (−)-abietic acid in 13 steps. Key features of the synthesis involved an oxidative [3+2] cycloaddition to i...

A photoredox catalyst free, visible-light-induced aerobic oxidative [2 + 3] cycloaddition reaction between glycine derivatives and styrene oxides has been disclosed that provides an efficient approach for the rapid synthesis of 1,3-oxazolidines under mild conditions. This photoinduced process is enabled by the formation of an electron donor-acceptor complex between glycine derivatives and benzyl iodides.

CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) are competitive fluorescent materials for lighting and displays owing to their excellent photophysical properties. However, the stability and optoelectronic performance of the perovskite NCs are severely limited by the highly dynamic binding feature of the present ligand strategy. Herein, a facile approach was employed to synthesize CsPbBr3 NCs with the assistance of the ionic liquid (IL) 1-butyl-3-methylimidazolium bromide ([Bmim]Br). By strictly controlling the addition dose of [Bmim]Br (nIL/nPb = 0.125) into the reaction precursor, it is possible to obtain the desired cube-shaped and monodisperse CsPbBr3 NCs with simultaneous enhancement of the storage and irradiation stability as well as photoluminescence quantum yields (PLQYs, ∼91%). Stability tests show that the emission intensity of the parent CsPbBr3 NCs drops to 50% of its initial emission intensity after storage under an open atmosphere for 91 days, while the sample prepared with the assistance of [Bmim]Br can maintain 82% of the PL intensity. Meanwhile, the modified CsPbBr3 NCs also present superior photo-stability, and still maintain 81% of the original PL intensity after continuous illumination under an ultraviolet lamp for 24 h, but the intensity of the parent CsPbBr3 NCs reduces to 35% of the original intensity. Through the morphology, composition, and luminescence kinetics evolution of CsPbBr3 NCs, these benefits were attributed to the modulation by [Bmim]Br, which could effectively provide Br ions for the formation and growth of NCs, resulting in the reduction of surface traps. Moreover, [Bmim]Br exhibited strong interactions with NCs, and the deprotonation of oleic acid (OA) was inhibited, resulting in the effective passivation of surface defects. Finally, CsPbX3 NCs with different compositions were obtained via a facile anion exchange reaction, leading to the tunable emission in the range of 462–665 nm and a wide colour gamut (129.65% NTSC standard). This work opens a new avenue for modulating the surface properties of CsPbX3 NCs, which will create opportunities for their application in the photoelectric field.

Psiguajdianone (1), a novel caryophyllene-derived meroterpenoid dimer, was isolated from Psidium guajava. The structure of 1 was determined by X-ray analysis and confirmed by total synthesis. Our synthetic strategy involves biomimetic cascade Knoevenagel condensation/hetero-Diels-Alder reaction and dimerization. Notably, the caryophyllene-derived meroterpenoids obtained during our synthesis were first identified as artifacts in the laboratory, and five of them were proven to be natural products present in the plant. Moreover, these compounds show significant anti-inflammatory activity.

Monoclinic bismuth vanadate (m-BiVO4) yellow pigments were synthesized by non-hydrolytic sol-gel (NHSG) route without any surfactants. The presence of Bi–O–V band in the sol and xerogel, indicates that the excellent atomic scale homogeneity could be reached. It is beneficial to achieve high purity m-BiVO4 phase and submicron scale particles (738 nm) with homogenous distribution at low temperature (400 °C), resulting in a brilliant yellow hue (b* = 71.18, hab = 89.73). These pigments have better chromatic performance than previously reported and commercially available BiVO4 yellow pigments. Meanwhile, the cytotoxicity of the pigment was tested in Mus musculus skin melanoma cells, and showed nontoxic for human cells, indicating its potential application in the high quality paints for automotive and architectural finishes.

Capitulactones A-C, three unprecedented 9-norlignans featuring a unique 3,5-dihydrofuro[2,3- d]oxepin-7(2 H)-one scaffold, were isolated from the roots of Curculigo capitulata. Their structures with absolute configurations were unambiguously established by a combination of spectroscopic data, ECD analysis, and total synthesis. Biomimetic total syntheses of three pairs of the corresponding enantiomers were achieved in 9-10 steps with overall yields of 14.8, 12.7, and 10.3%, respectively. Notably, the unique scaffold of the common western hemisphere of the molecules was constructed by using the oxidation-reduction strategy from benzodihydrofuran.

The first gram-scale asymmetric total synthesis of (+)- and (-)-codonopiloneolignanin A has been achieved from multisubstituted cinnamaldehyde in four steps with 37% overall yield. The synthetically challenging tricyclic [5, 3, 0, 03,8] decane skeleton was efficiently constructed via a highly enantioselective dimerization of multisubstituted cinnamaldehyde, followed by a sequence of cascade reactions including Prins cyclization, cation mediated cyclization, and deprotection. Furthermore, the scope of NHC-catalyzed/Ti(IV)-mediated synergistic control multisubstituted cinnamaldehyde dimerization was investigated. Significantly, the bioactivity of codonopiloneolignanin A and its enantiomer, particularly scarce in nature, was tested and showed good anticancer activity.

Plant derived carbon was utilized as a new financial and environmental friendly colorant in the synthesis of zircon encapsulated carbon pigment (C@ZrSiO4) via non-hydrolytic sol-gel method. After calcining, nature plants, i.e. sisal and bamboo leaves, were carbonized and occluded in ZrSiO4 matrix. The FT-IR and XRD results demonstrated that the plants were not affect the non-hydrolytic sol-gel polycondensation reaction, resulting in the pure ZrSiO4 formation. Both inclusion pigments presented deep black hue, i.e. L∗ = 34.93 and 33.02 for sisal and bamboo leaves, respectively, which was contributed to the homogeneous pore-size distribution and high carbon yield of the plants. These pigments have many distinguished advantages including low cost, high chromatic performance and excellent thermal stability, making them promising candidates for ceramic decoration.

A facile approach towards photoluminescent (PL) Cu-In-Zn-S quantum dots (CIZS QDs) has been developed, comprising microwave treatment with the assist of room-temperature ionic liquid (RTIL). Because of its high polarizability, RTIL served as a microwave absorbent, which resulted in the increase of the instantaneous nucleation rate and the rapid synthesis of CIZS QDs at low temperature. Moreover, the surface decoration of QDs with RTIL can passivate the surface defects greatly. The PL intensity of the CIZS QDs depends on the anion species, alkyl chain length of the RTIL, and the metal element ratios of the QDs. On the basis of the variable PL peak position and extended luminescence lifetime of the CIZS QDs, the superior emission behavior of the QDs was confirmed by surface etching with fluoride produced by the hydrolysis of RTIL 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4 ). Moreover, the intermediate alkyl chain length of the RTIL can avoid aggregation, which results in the construction of CIZS QDs with homogenous size distribution. The shape-controlled CIZS QDs show a broadened tunable emission peak from 677 to 579 nm compared with that of QDs prepared by a conventional one-pot method by mixing the raw materials. CIZS QDs also exhibit a high quantum yield (QY) of 24.1 % after coating with a ZnS shell. This method is expected to be a useful technique for the rapid synthesis of multiple QDs with a wider range of emission wavelengths and higher QY for a variety of applications.

Yellow inorganic pigments PrxZr1-xSiO4 (x = 0–0.08) have been prepared by a novel non-hydrolytic sol-gel (NHSG) method at 750 °C for 2 h. Replacing Pr4+ for Zr4+ in ZrSiO4 increased the cell volume and changed the color from white to yellow gradually. The Si―O―Zr and Si―O―Pr bands were observed in the FT-IR spectra of xerogel, indicating it could reach homogeneous mixing at the atomic level. Therefore, it promoted the solid solution reaction between Pr and zircon at low temperature. The samples exhibit high doping limitation (x = 0.08) and brilliant yellow hue (b* = 69.48) in contrast with the previously reported praseodymium zircon yellow pigments. The intense of yellow hue was increased with increasing the Pr doping content due to the increase of Pr4+/Pr3+ species. After applying on bisque ceramic tiles, the pigment exhibited excellent coloration, high thermal stability and low solubility in molten glazes, indicating its potential application in ceramic decoration.

BACKGROUND Whey acidic protein/four-disulfide core domain 21 (Wfdc21), also known as Lnc-DC, it has been reported to be correlated with immune response. However, the role of Wfdc21 in the pathogenesis of sepsis is still unknown. In the present study, we aimed to investigate the role of Wfdc21 in the pathogenesis of sepsis. MATERIAL AND METHODS The cecal ligation and puncture (CLP)-induced sepsis model was established in Balb/c mice. Animals were euthanized 4, 8, 16, or 24 h after CLP. The glycogen distribution in the kidney and liver was checked by Periodic acid-Schiff (PAS) staining. Changes in the serum interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) concentrations were monitored with ELISA, and Wdfc21 expression was determined by qPCR. Mouse macrophage-like RAW264.7 cells were treated with different doses of lipopolysaccharide (LPS) from Escherichia coli to mimic sepsis in vitro. Western blot analysis was performed to confirm whether LPS-induced in vitro sepsis was correlated with the involvement of the Stat3/TLR4 signaling pathway. In addition, RAW 264.7 cells were infected with lentiviruses containing Wfdc21 shRNA to further confirm the role of Wfdc21 in the pathogenesis of sepsis. RESULTS We found that Wfdc21 level was elevated in the CLP-induced animal model and LPS-treated RAW264.7 cells. Furthermore, the downregulation of Wfdc21 modulated the concentration of pro-inflammatory factors in LPS-treated macrophages, such as IL-1β and TNF-α, in LPS-treated macrophages. This regulatory effect was mediated through the Stat3/TLR4 signaling pathway, since Wfdc21 can regulate p-Stat3 and TLR4 levels in LPS-treated macrophages. CONCLUSIONS Wfdc21 plays a critical role in the pathogenesis of sepsis and may provide a therapeutic target for sepsis treatment.

Concise total syntheses of callistrilones A-E have been achieved from 7 and commercially available α-phellandrene (8). The synthetic strategy, which was primarily inspired by the biogenetic hypothesis, was enabled by an oxidative [3 + 2] cycloaddition followed by a Michael addition and an intramolecular nucleophilic addition to construct the target molecules. Moreover, viminalin I was also synthesized, and its absolute configuration was unambiguously confirmed.

Polymer spheres with tunable particle size were synthesized by hydrothermal method derived from sucrose. Afterwards, zircon was coated on their surface to form the zircon encapsulated carbon (C@ZrSiO4) black pigment after calcination. The corresponding relationship between the particle size of polymer spheres and the chromaticity of C@ZrSiO4 pigments was investigated. The results revealed that the chromatic performance of C@ZrSiO4 pigment can be significantly improved by decreasing the colorant size and the relationship between them was approximately linear. The pigment exhibits deep black hue, as L∗ = 41.04, a∗ = 1.01, b∗ = 3.22, with the colorant size of 123 nm. Moreover, it also presents excellent thermal and chemical stability, indicating its potential candidate for ceramic decoration.

Salyunnanin A and hassanane, two C23 terpenoids, were achieved from (+)-carnosic acid in 6 and 5 steps, respectively. The synthetic strategy was primarily inspired by the biogenetic hypothesis and provided access to the natural products via elimination, double Michael-type addition in one pot to prepare the corresponding 6,20-epoxyabietanes, and bismuthonium ylide induced ring expansion of o-quinone to construct 2-acyl-3-hydroxytropone.

A concise total synthesis of myrtucommulone K, N and O have been developed in 4 steps from commercially available materials. The synthetic strategy was inspired primarily by the biogenetic hypothesis and firstly enabled via a reduction, dehydration sequence for preparing isobutylidenesyncarpic acid followed by a hetero-Diels-Alder reaction to disclose the target moleculars. In this approach the exocyclic double bond of (−)-β-caryophyllene was more active than the endocyclic one in hetero-Diels–Alder reaction as the dienophile. The route is protecting-group-free, concise step, redox and pot economy.

Synthesis of water-soluble I-III-VI type quantum dots (QDs) with high luminescence performance in efficient pathways still remains a tremendous challenge. In this study, water-soluble Ag-In-Zn-S (AIZS) QDs were prepared via the room temperature ionic liquids (RTILs) assisted hydrothermal method. The experimental results showed that the RTIL 1-methylimidazolium tetrafluoroborate ([Mim]BF4) played an important role in the phase structure, morphology, and optical properties of the AIZS QDs due to its high polarity and low surface tension, which was beneficial to the nucleation, growth, and surface modulation of QDs, resulting in the improvement of quantum yield (QY) from 23.2% to 28.9%. Moreover, the AIZS QDs exhibited long fluorescence lifetimes of 472.3 ns, further demonstrating the successful passivation of the trap states of QDs. Furthermore, the emission wavelength of AIZS QDs could be adjusted from 608 to 525 nm by tuning Ag/Zn ratios. Finally, a white light-emitting diode (WLED) based on AIZS QDs and green Lu3Al5O12:Ce3+ phosphor was successfully fabricated, which showed high luminous efficiency of 85.2 lm/W, color rendering index (CRI) of 62.2, and the correlated color temperature (CCT) of 6153 K, indicating the promising prospects of AIZS QDs’ application in photoelectric devices.

A highly efficient synthesis of the DEFG-ring system of rubriflordilactone B via polar-radical-crossover cycloaddition and carbonyl allylation/lactonization is described.

A highly stereocontrolled synthesis of paeoveitol has been developed in 26% yield, in 7 steps from commercially available materials. The synthetic strategy was inspired primarily by the biogenetic hypothesis and was enabled by hetero-Diels-Alder cycloaddition to construct the target molecular framework.

Perovskite nanocrystals (NCs) are promising materials for light-emitting diodes (LEDs) owing to their unique optoelectrical properties. However, the organic long-chain ligands act as insulating layers on NC surface, causing the low carrier transport capability and poor performance of LEDs. Herein, a novel strategy was proposed to facilitate the carrier transport for enhancing the performance of perovskite light emitting diodes (PeLEDs). Ionic liquid (IL) 1-ethyl-3-methylimidazolium bromide [Emim]Br was introduced into the synthesis process of CsPbBr3 NCs, which could improve the emission intensity of NCs significantly. Furthermore, [Emim]Br also possessed the characteristic that facilitated the transportation of carriers, resulting in the enhancement of external quantum efficiency (EQE) of PeLEDs from 0.38% to 1.03%. These results demonstrate that the novel strategy opens up new avenue for boosting the PeLED performance, which will promote the commercial applications in future high-definition displays.

The bowl-shaped tricyclo[6.3.1.04,12]dodecane moiety is the core feature of cephalotane-type diterpenoids. As part of our efforts directed towards a total synthesis of mannolide B, the bowl-shaped tricyclo[6.3.1.04,12]dodecane skeleton, a common intermediate of cephalotane-type diterpenoids bearing up to five contiguous stereocenters including two quaternary carbon centers had been constructed. The synthetic strategy was enabled by an efficient application of oxidative dearomatization/intramolecular Diels-Alder reaction to access highly functionalized building block with the tricyclo[5.2.2.02,6]undecane unit from commercially available materials. The key feature was firstly used the cyclic olefins with secondary alcohol as dienophile for the intramolecular inverse electron demand Diels-Alder reaction. Further synthetic studies led to construct ring D by a regioselective Aldol reaction.

A concise total synthesis of tetranorsesquiterpenoids applanatumol Z5 (3), possessing unique 6/5/5 ring system was disclosed with 7-step in 5-pot from commercially available starting materials. The key elements of the synthesis included an unexpected intramolecular dithiolane with alcohol oxidative coupling/deprotection sequence to create the unsaturated lactone as dienophile and a regioselective Diels-Alder reaction to assemble the 6/5/5 tricyclic scaffold including two vicinal quaternary carbon stereocenters. Late stage the diastereo- and regioselective carbonyl reduction led to achieve the total synthesis of (±) applanatumol Z5 (3).

I–III–VI quantum dots (QDs), as a new class of light-emitting materials, have aroused a great of attention for an impressive variety of applications. A facile one-pot approach was employed to synthesize highly luminescent Cu–In–Zn–S/ZnS (CIZS/ZnS) core/shell QDs. It was found that the CIZS/ZnS QDs prepared using sodium sulfide as sulfur source exhibited the strongest emission due to its highest chemical reactivity as compared to thiourea and thioacetamide. The combination of GSH content and pH value played a crucial role in the growth of ZnS shell, which was responsible for the bright emission of QDs. The surface defects of QDs could be effective passivated by GSH, which exhibited a significant improvement of emission intensity. The optimum pH value of 7 was also established due to the fact that the deprotonized sulfhydryl group of GSH molecule strongly coordinated with Zn2+ at neutral pH value. Moreover, the particle size and composition of the CIZS/ZnS QDs can be well adjusted by tuning the nZn/nCuInZn ratios. The maximum quantum yield (QY) of CIZS/ZnS QDs increased from 5.95% to 26.12%, accompanying by the improvement of the radiative decay rate from 1.90 × 105 to 5.64 × 105 s−1. Furthermore, a blue LED-pumped white light-emitting diode (WLED) device was realized by combining yellow-orange CIZS/ZnS QDs with green Lu3Al5O12:Ce3+ phosphor, achieving a luminous efficacy (LE) of 66.9 lm/W, and color rendering index (CRI) of 87.2, which demonstrated their great application potential in solid-state lighting field.

A highly stereocontrolled construction of the C-5-epi ABCDE-ring system of rubriflordilactone B has been developed. The present synthesis features a convergent strategy to construct the C-5-epi AB-ring utilizing Mukaiyama-Michael reaction and forge the CDE ring in one step using intramolecular [2 + 2 + 2] cycloaddition of triynes.

A concise total synthesis of (±)-pisiferin has been accomplished from commercially available compounds α-cyclocitral ( 9 ) and 4-bromo-2-isopropylphenol ( 10 ) via Suzuki coupling and F–C alkylation as key reaction in five steps with an overall yield of 22%. The feature of this concise synthesis is a convergent strategy coupled by Suzuki reaction. This work not only provides a strategy to approach the total synthesis of pisiferin itself but also serves as an additional correlation origin to which many related icetaxane-type diterpenes can be referred.

The biomimetic total synthesis of potential anti-HIV (−)-isatisine A, a novel alkaloid with an unprecedented fused tetracyclic skeleton, was accomplished in eight steps from indole and known 4,6- O -isopropylidene-protected glucal. The synthetic strategy was inspired primarily by the proposed biogenetic hypothesis that indole C -furanoside would be derived from indole C -glucoside via a ring contractive benzilic acid rearrangement. The biogenetic hypothesis was enabled by model studies: the O -glucoside was converted to O -furanoside via a benzilic acid rearrangement.

A concise and facile synthetic protocol for the construction of the 2-γ-lactone chromanone skeleton has been achieved through a TMSI-promoted diastereoselective vinylogous Michael addition of siloxyfuran to 2-substituted chromones. The applicability of this method is demonstrated through the rapid access to the total syntheses of (±)-microdiplodiasone, (±)-lachnone C, and (±)-gonytolides C and G.

α-Enamino esters were efficiently prepared directly from readily available α-amino acid esters using a Cu(II)-promoted dehydrogenation with broad functional group tolerance and good to excellent yields. Moreover, the first application of α-enamino esters for the synthesis of polysubstituted pyrroles was achieved using an oxidative coupling with alkynes under Cu(II)-promoted conditions via intermolecular carbometalation of the alkyne in high yields.

One-pot, atom-economical, catalyst-free and tri-component domino reactions are applied to the diversity-oriented synthesis (DOS) of disubstituted piperazine derivatives under mild conditions with moderate to high yields. This protocol exhibits potential applicability in the synthesis of pharmaceuticals, liquid crystals, complexes, etc. Because of its operational simplicity and convenience, it may be suitable for application in large-scale synthesis.

Przewalskin A, a novel C23 terpenoid with anti-HIV-1 activity from Salvia przewalskii Maxim, was formed in 10 steps via isorosmanol from (+)-carnosic acid. The synthetic strategy was inspired primarily by the biogenetic hypothesis and was enabled by epoxidation, epoxide ring opening, and lactonization in one pot to prepare the 11,12-dimethoxy isorosmanol, and bismuthonium ylide-induced ring expansion of o-quinone to construct the 2-acyl-3-hydroxytropone.

Ce0.8Sm0.2O2 − δ–LnBaCo2O5 + δ (SDC-LnBCO, Ln=La, Nd, Sm, and Y) composites were prepared and characterized as dense ceramic membranes for oxygen separation. Ce0.8Sm0.2O2 − δ (SDC) shows a good chemical compatibility with LaBaCo2O5 + δ (LBCO), NdBaCo2O5 + δ (NBCO), and SmBaCo2O5 + δ (SBCO), while a little of impurity is detected in the sample with YBaCo2O5 + δ (YBCO). The SDC-SBCO and SDC-YBCO samples exhibit larger grain size than SDC-LBCO and SDC-NBCO. The incorporation of SDC increases the structural stability and decreases the thermal expansion coefficient of LnBCO at high temperature. The oxygen permeation flux of SDC-LnBCO dual-phase membrane decreases with decreasing Ln3+ radius, which is 2.57 × 10−7, 1.58 × 10−7, 8.05 × 10−8, and 7.57 × 10−8 mol cm−2 s−1 at 925 °C for SDC-LBCO, SDC-NBCO, SDC-SBCO, and SDC-YBCO membranes, respectively. Increasing the flow rate of feeding and sweeping gas can create oxygen partial pressure gradient, and thus, increase the oxygen permeability. These results indicate that SDC-LBCO and SDC-NBCO composites are promising candidates for oxygen permeation membrane.

The suitability of double perovskite oxides of composition Sr2Mg1–xNixMoO6−δ (SMNM, x = 0–0.9) as anode materials for solid oxide fuel cells (SOFCs) was evaluated. Single double perovskite structures could be obtained up to x = 0.9 in syntheses at ambient atmosphere. However, after reduction at 800 °C, trace amounts of impurities were detected in the sample with x = 0.9, suggesting that the upper limit for the Ni content (x) in SMNM is less than 0.9 under SOFC operating conditions. The electrical conductivity of SMNM increases with increasing Ni content because of the increase in the concentration of electronic defects, [MoMo6+5+′], and the decreased band gap energy, as revealed by first-principles calculations. The substitution of Ni can facilitate the charge-transfer process of the electrode reaction, decrease the polarization resistance, and thus increase the power density of a single cell. X-ray photoelectron spectroscopy and temperature-programmed reduction measurements were used to explain the reaso...

An effective and concise approach to synthesis of tetrasubstituted pyrroles from readily available amino acid esters by the promotion of Cu(OAc)2 in conjunction with Mn(OAc)3 has been developed. This reaction proceeds through multiple dehydrogenations, deamination, and oxidative cyclization. This oxidized system tolerates substrates bearing various electron-donating or electron-withdrawing groups. With this methodology, several key intermediates of natural products have been effectively prepared, and the total syntheses of lycogarubin C and chromopyrrolic acid have been completed in high efficiency.

A concise total synthesis of przewalskin B was accomplished from readily available diene 7. Key features of the synthesis involved a Diels-Alder reaction to install the A ring, a Claisen-Johnson rearrangement to establish the spiro-quaternary center, and a ring-closing metathesis (RCM) of a sterically crowded system to construct the cyclic enone moiety.

Domino nucleophilic addition was used for four-component Al2O3-catalyzed environmentally friendly synthesis of polysubstituted β-cyanopropan-1-one. Domino nucleophilic addition involves removal of the cyano group linked to active methylene by the action of KF, and direct addition to enones. The reaction's capability for nucleophilic attack is F− > CN− in DMF. The use of low-toxicity reagents hints that the reaction is more environmentally friendly than traditional approaches.

A novel and efficient one-pot method has been developed for the synthesis of 2-substituted-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one derivative by the combination of [3 + 3] cycloaddition, reduction, deamination reactions. The fused heterocyclic compounds 2-substituted-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-ones was synthesized by the diversity-oriented catalysis. As an extension of the synthetic methodology, some 4H-pyrido[1,2-a]pyrimidin-4-one 4a–c was synthesized. The π–π accumulation structure of supramolecular self-assembly was discussed in the crystal.

Dual-phase oxygen permeation membrane has become much attractive due to its tailorable properties. On the premise of forming percolative network separately, decreasing the volume percentage of electronic conducting phase can increase the oxygen permeability of dual-phase membrane. However, the conventional ceramic route limits the decrease in threshold of the content of electronic conducting phase. In this work, a coating strategy is employed to fabricate a novel dual-phase membrane with 20 vol.% PrBaCo2O5+δ (PBCO) dispersing in 80 vol.% Ce0.8Sm0.2O2−δ (SDC) matrix, where the fiber-shaped PBCO forms percolative network and provides sufficient electronic conductivity. The prepared SDC-PBCO membrane with 1 mm thickness exhibits very high oxygen permeability, 3.81 × 10−7 mol cm−2 s−1 at 940 °C, due to the high volume percentage of SDC. This preparation strategy can be applied to other dual-phase membranes to improve the oxygen permeation performance.

The anode materials La 0.3 Sr 0.7 Ti 1− x Cr x O 3− δ (LSTC, x = 0, 0.1, 0.2) with cubic structure were prepared via solid state reaction route. The influence of Cr content on the properties of LSTC as anode and interconnect materials for solid oxide fuel cells (SOFCs) was investigated. The Cr-doping decreased the lattice parameter while increased the sinterability of LSTC materials. The total electrical conductivity decreased with Cr doping level, from 230 S cm −1 for x = 0 to 53 S cm −1 for x = 0.2. The total electrical conductivity exhibited good stability and recoverability in alternative atmospheres of air and 5% H 2 /Ar, showing excellent redox stability. The cell testing showed that the anode performance of LSTC was enhanced somewhat by Cr doping. The present results indicated that the prepared La 0.3 Sr 0.7 Ti 1− x Cr x O 3− δ can be potential anode and interconnect materials for SOFCs.

A novel and efficient approach towards α-amino esters as synthons for polysubstituted NH pyrroles is presented.

A porous PrBaCo 2 O 5+ δ or Ce 0.8 Sm 0.2 O 2− δ –50 vol.% PrBaCo 2 O 5+ δ (SDC–PBCO (5/5)) layer was deposited on dense Ce 0.8 Sm 0.2 O 2− δ –40 vol.% PrBaCo 2 O 5+ δ (SDC–PBCO (6/4)) membrane (450 μm) to enhance the oxygen permeability by increasing the surface area contacting with air. The oxygen permeation flux was measured in the temperature range of 825–945 °C. The results revealed that the oxygen permeation performance of Ce 0.8 Sm 0.2 O 2− δ –PrBaCo 2 O 5+ δ membranes can be significantly enhanced by coating SDC–PBCO (5/5) porous layer alone on the surface of feed side. The thickness of modification layer has obvious effect on the permeability of surface modified membrane. The modification on the feed side has much better effect than that on the permeate side. At 945 °C, the oxygen permeation flux of dense SDC–PBCO (6/4) membrane modified by porous SDC–PBCO (5/5) layer is 3.56 × 10 −7 mol cm −2 s −1 , 26% higher than that of the unmodified one.

A one-pot synthesis of aurones from substituted acetophenone and benzaldehyde has been developed on the basis of an improved Algar–Flynn–Oyamada reaction. By using this method, several aurones were prepared in three steps from commercial starting materials. The usefulness of this one-pot strategy was confirmed by a synthesis of aureusidin, an inhibitor of iodothyronine deiodinase, in 41% overall yield. In comparison with a two-step synthesis of this product from the same substrates, the one-pot strategy was more effective, giving a higher yield and requiring fewer and simpler operations.

Double-perovskite materials of composition Sr2Mg1–xCoxMoO6−δ (SMCMO, x = 0 to 0.7) were evaluated as potential SOFC anode materials. Their lattice structures, electrical and ionic conductivity, thermal expansion coefficient (TEC), and electrochemical performance were investigated as a function of Co content. Co doping was found to increase the TEC of the Sr2MgMoO6−δ material; however, the TEC was within the range of the commonly used La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte. SMCMO also showed good chemical compatibility with the LSGM electrolyte at temperatures below 1300 °C. Both the electronic and ionic conductivity increased with increasing Co doping. To investigate the effect of Co doping on the conduction properties of SMCMO, we performed first-principle calculations. From these results, the weak Co–O bond is considered to be responsible for the enhanced ionic conductivity of SMCMO materials. The substitution of Co was also found to increase the sinterability of SMCMO, resulting in a decrease in t...

A novel dual-phase oxygen permeation membrane based on ion-conducting Ce 0.8 Sm 0.2 O 2−δ (SDC) and mixed conducting PrBaCo 2 O 5+δ (PBCO) is presented. There is no obvious reaction between the two phases under preparation and oxygen permeation conditions. The percolative network of mixed conducting phase PBCO can be formed in SDC-PBCO composite when the ratio of PBCO is not less than 40 vol.%. Above this threshold, the oxygen permeability of SDC-PBCO membrane increases with increasing SDC content. Compared with pure PBCO membrane, the oxygen permeability of percolative SDC-PBCO composites is improved due to the 3D diffusion ability of SDC, which can shorten the tortuosity of the oxygen diffusion path in layered PBCO. The maximum oxygen flux based on 0.6-mm-thick SDC-PBCO (6/4) is 2.38 × 10 −7 mol cm −2 s −1 at 925 °C. The dependence of the oxygen permeation flux on the membrane thickness demonstrates that the bulk diffusion is the limiting step at thickness higher than 0.8 mm and the surface exchange may play an important role when the thickness is below that. Incorporation of SDC into PBCO can not only improve the oxygen permeability but also enhance the structural stability. The SDC-PBCO (6/4) dual-phase membrane is a promising candidate for oxygen separation application.

2-Aryl-3H-indol-3-ones reacted with aldehydes or ketones in the presence of L -proline as a catalyst to give the corresponding aza-quaternary carbon addition product in good yield with moderate to excellent regioselectivity and enantioselectivity. The system was applied to the reaction of 2-(2-bromo-phenyl)-3H-indol-3-one and acetaldehyde to give 2-[2-(2-bromophenyl)-3-oxoindolin-2-yl]acetaldehyde, which is a precursor for the synthesis of some alkaloids such as hinckdentine A.

Aluminum doped Sr2MgMoO6-δ (SMMO) was synthesized via citrate-nitrate route. Dense samples of Sr2Mg1-xAlxMoO6−δ (0 ≤ x ≤ 0.05) were prepared by sintering the pellets at 1500 °C in air and then reducing at 1300 °C in 5%H2/Ar. The electrical conductivity strongly depended on the preparing atmosphere, samples reduced in 5%H2/Ar exhibited higher conductivity than those unreduced. Al-doping increased remarkably the electrical conductivity of Sr2Mg1-xAlxMoO6−δ. The reduced samples displayed a relatively stable electrical conductivity under oxygen partial pressure (Po2) from 10−19 to 10−14 atm at 800 °C, and exhibited an excellent recoverability in electrical conductivity when cycled in alternative air and 5%H2/Ar atmospheres. Sr2Mg0.95Al0.05MoO6−δ material showed a good chemical compatibility with LSGM and GDC electrolytes below 1000 °C, while there was an obvious reaction with YSZ. Al-doping improves the anode performance of SMMO in half-cell of Pt/Sr2Mg1-xAlxMoO6−δ∣GDC∣Pt in H2 fuel. The present results demonstrate that Sr2Mg1-xAlxMoO6−δ is a potential anode material for intermediate temperature-Solid Oxide Fuel Cells (IT-SOFCs).

Unexpected products containing acyl-substituted unsaturated seven-membered carbocycle were synthesized by FeCl 3 -promoted intramolecular Prins cyclization of alkynyl-dimethylacetals in good yields. It is remarkable that the synthesized 7-exocyclic vinyl cations generated as a result of Prins-type cyclization were trapped by H 2 O (no halogen ion) in CH 2 Cl 2 to give the corresponding enol derivatives. Those enol derivatives underwent enol-keto tautomerism and then eliminated one molecule of MeOH to give the corresponding acyl-substituted unsaturated seven-membered carbocycle.

The enantioselective syntheses of (-)-spirooliganones A and B have been accomplished in eight steps from commercially available starting materials. Noteworthy transformations include a three-component hetero-Diels-Alder cycloaddition to construct the tetracyclic core of spirooliganones, a Sharpless asymmetric dihydroxylation, and a tandem oxidative dearomatization/cyclization to build the oxa-spiro cyclohexadienone skeleton. The straightforward syntheses were performed without protecting groups.

A-site-deficient (La0.3Sr0.7)1−xTiO3−δ materials were synthesized by conventional solid-state reaction. The A-site deficiency limit in (La0.3Sr0.7)1−xTiO3−δ was below 10 mol% in 5%H2/Ar at 1500 °C. A-site deficiency level promoted the sintering process of (La0.3Sr0.7)1−xTiO3−δ. The ionic conductivity increased but the electronic conductivity decreased with increasing A-site deficiency level. The ionic conductivity of (La0.3Sr0.7)0.93TiO3−δ sample was as high as 0.2–1.6 × 10−2 S/cm in 500–950 °C and 1.0 × 10−2 S/cm at 800 °C, over twice of La0.3Sr0.7TiO3−δ. Its electrical conductivity was in the range of 83–299 S/cm in 50–950 °C and 145 S/cm at 800 °C. A-site deficiency improved the thermal stability of (La0.3Sr0.7)1−xTiO3−δ and ensured the material with a stable electrical performance in different atmospheres.