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A Cu-catalyzed cascade oxidative radical process of β-keto sulfones with alcohols has been achieved by using oxygen as an oxidant. In this reaction, β-keto sulfones were converted into sulfinate esters under the oxidative conditions via cleavage of C-S bond. Experimental and computational studies demonstrate that a new pathway is involved in this reaction, which proceeds through the formation of the key four-coordinated CuII intermediate, O-O bond homolysis induced C-S bond cleavage and Cu-catalyzed esterification to form the final products. This reaction provides a new strategy to sulfonate esters and enriches the research content of C-S bond cleavage and transformations.

The Jiangjunshan and Dakalasu alkali-feldspar granites are located in the central part of the Chinese Altay orogen. In this paper, we present detailed geochemical, zircon U-Pb, and Hf isotopic data of these granites. The Jiangjunshan and Dakalasu alkali-feldspar granites show a high content of SiO2 (72.05-73.27 and 69.55-71.04wt%, respectively), total alkalis (Na2O+K2O=8.41-8.71 and 7.24-8.66wt%, respectively), and high-field strength elements (Zr+Nb+Ce+Y=400.3-482.9 and 156.7-339.3ppm, respectively), as well as high Ga/Al ratios (10,000xGa/Al=3.46-4.19 and 2.62-3.28, respectively) and depletion in Ba, Nb, Sr, and Ti, showing geochemical characteristics similar to those of A-type granites. Zircon U-Pb dating of the Jiangjunshan and Dakalasu alkali-feldspar granites yielded weighted mean dating Pb-206/U-238 ages of 268.3 +/- 1.9 and 270.4 +/- 1.9Ma, respectively, indicating that these granites intruded during the Permian. The Jiangjunshan and Dakalasu alkali-feldspar granites show highly variable zircon epsilon(Hf)(t) values ranging from -7.0 to +5.6, implying that these granites originated from a mixing of mantle-derived magma with crustal materials. Our data on the Jiangjunshan and Dakalasu alkali-feldspar granites, coupled with previous studies of Permian magmatism and metamorphism, suggest that the tectonic regime was in a postcollisional extensional environment in the Chinese Altay orogen during the Permian. Therefore, the change in stress from compression to extension and asthenospheric upwelling triggered by slab break-off plays a significant role in the generation of Jiangjunshan and Dakalasu alkali-feldspar granites.

Several chiral BINOL-derived bisoxazoline (BOX)/copper(II) complexes were synthesized and evaluated as catalysts for the Friedel–Crafts reaction of indoles with isatin-derived β,γ-unsaturated α-keto esters. The resulting bis-indole products bearing a quaternary stereocenter were obtained in excellent yields and enantioselectivities. Additionally, the desired products were practically transformed to α-amino esters, α-hydroxy esters and α-keto amides. It is noteworthy that this catalytic procedure was conducted with a catalyst loading of 0.5 mol% without any discernible decrease in the reactivity or enantioselectivity.

One peculiar type of aza-hetero-imidazolidinyl spirooxindole derivatives was efficiently constructed by the three-component [2+2+1] cascade reaction of 1,4-oxazepines with diazo-oxindoles. Iron(II) trifluoromethanesulfonate [Fe(OTf)2] or p-toluenesulfonic acid monohydrate (p-TsOH⋅H2O) proved to be optimal catalysts for this transformation, providing the desired products in high yields (up to 94 %) with excellent diastereoselectivity (up to 99:1 dr). Experimental studies showed that the reaction rate of Bronsted acid catalysis was faster than that of Lewis acids. Furthermore, the mechanism was theoretically investigated for Bronsted acid as the catalyst and a reaction pathway was proposed. DFT calculations suggested that the diazo-oxindole can act as a 1,3-dipole to add to a C=N double bond of 1,4-oxazepine, which forms a 4,5-dihydro-1H-1,2,3-triazole intermediate. Subsequently, the releasing of N2 is the rate-limiting step of the whole catalytic cycle.

A multimodal cancer therapeutic nanoplatform is reported. It demonstrates a promising approach to synergistically regulating the tumor microenvironment. The combination of intracellular reactive oxygen species (ROS) generated by irradiation of photosensitizer and endoplasmic reticulum (ER) stress induced by 2-deoxy-glucose (2-DG) has a profound effect on necrotic or apoptotic cell death. Especially, targeting metabolic pathway by 2-DG is a promising strategy to promote the effect of photodynamic therapy and chemotherapy. The nanoplatform can readily release its cargoes inside cancer cells and combines the advantages of ROS-sensitive releasing chemotherapeutic drugs, upregulating apoptosis pathways under ER stress, light-induced generation of cytotoxic ROS, achieving tumor accumulation, and in vivo fluorescence imaging capability. This work highlights the importance of considering multiple intracellular stresses as design parameters for nanoscale functional materials in cell biology, immune response, as well as medical treatments of cancer, Alzheimer's disease, etc.

A series of chiral thiopyrano-indoles (III) and (V) is readily obtained by an enantioselective cyclization of indoline-2-thiones (I) with dinitriles (II) and (IV).

A diastereo- and enantioselective domino Michael-cyclization-tautomerization reaction of isatylidene malononitriles (I) and (IV) with α,α-dicyanoalkenes catalyzed by a chinchona alkaloid-derived bifunctional catalyst is reported.

The rigid nano-silica and soft nano-rubber toughening effects on neat epoxy under impact loading in a range of −50 to 80 °C were investigated. Nanosilica particles (20 nm) toughened neat epoxy at all temperatures with a maximum toughening efficiency at −50 °C and lower efficiency at elevated temperatures. In contrast, except at −50 °C, nano-rubber particles (100 nm) showed the deterioration effect on the impact fracture toughness of epoxy resin. Scanning electron microscopy examinations revealed that the crack pinning and local epoxy deformation induced by rigid particles in term of nano-silica/epoxy and nano-rubber/epoxy interfacial debonding (at −50 °C) led to positive toughening efficiency on neat epoxy. However, at 20 and 80 °C, the rubber cavitations/void plastic growth was significantly suppressed under the impact loading, which led to the negative toughening efficiency on epoxy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45319.

Pyranonaphthoquinone units are common in molecular structures with significant biological and pharmaceutical activities. Herein, the organocatalytic asymmetric cascade Michael cyclization reaction of 2-hydroxynaphthalene-1,4-diones to isatylidene malononitriles has been developed, which provided the desired spiro[4H-benzo[g]chromene-indoline] derivatives in up to 99% yield with up to 99% ee. To illustrate the potential utility of these products, a further transformation was conducted to give a spiropoly­heterocyclic compound in moderate yield without loss of enantioselectivity (>99% ee). Biological evaluation of these spiro[benzo[g]chromene-indoline] derivatives has revealed excellent antiproliferative activity against a number of cancer cell lines, with a high inhibition rate ranging from 93% to 99% at a concentration of 50 μM.