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This work describes a base-mediated borylsilylation of benzylic ammonium salts to synthesize geminal silylboronates bearing benzylic proton under mild reaction conditions. Deaminative silylation of aryl ammonium salts was also achieved in the presence of LiOtBu. This strategy which is featured with high efficiency, mild reaction conditions, and good functional group tolerance provides efficient routes for late-stage functionalization of amines.

Leaching technique was mostly carried out on submarine rock powder to minimize or eliminate secondary effect of seawater interaction on Sr and Pb isotope magmatic signatures. However, the effect of leaching on trace element contents is comparatively poorly established. To investigate such effects, we have compared trace element and Nd-Pb isotopic data for acid leached ∼290 Ma Keping basalts in the Tarim Large Igneous Province (NW China) with unleached data on the same rocks. Rare earth elements (REE), Y, Th and U contents of leached sample grains (0.6–1.0 mm size) are 10–65% lower than those of unleached grains of the same sample, whereas other trace elements are not affected. Sm/Nd, Lu/Hf, U/Pb and Th/Pb ratios are fractionated by acid leaching between leached and unleached sample grains. Nd isotope values are unaffected by leaching, but 208Pb/204Pb and 206Pb/204Pb values of leached samples are significantly lower than those of unleached samples. X-ray diffraction results suggest that removal of secondary epidote during the acid leaching process could result in the fractionation of REE, Y, Th and U contents, and Sm/Nd, Lu/Hf, U/Pb and Th/Pb ratios, and 208Pb/204Pb and 206Pb/204Pb values. These results suggest that when the samples have been leached with strong acid (>1N HCl), their trace element cannot be used to trace the sources and petrogenesis. If leaching is applied to old (e.g., >100 Ma) continental basalts in order to eliminate contamination during sample collection, storage, sawing and crushing, Th/Pb and U/Pb ratios used to calculate the initial Pb isotope values, should be obtained on the same leached samples. Keywords: Tarim Large Igneous Province, Trace element, Nd-Pb isotopes, Alteration, Acid leaching

Phytochemical investigation on the 95% EtOH extract of the Traditional Chinese Medicine (TCM) Euphorbia royleana (Ba-wang-bian in Chinese) led to the isolation of 11 diterpenoids (1–11) and two triterpenoids (12 and 13). Among them, compounds 1 and 2 were new ingenane and ingol diterpenoids, respectively. Their structures were elucidated by a combination of spectroscopic analyses (1 D and 2 D NMR, HRMS, ECD, UV, and IR data) and chemical methods. Compounds 12 and 13 exhibited moderate cytotoxicities in vitro against human lung cancer cell line A549 with IC50 values of 14.84 ± 0.56 and 27.11 ± 1.65 µM, respectively.

Tremella fuciformis is an important edible mushroom that has been widely cultivated and used as food and medicinal ingredient in traditional Chinese medicine. In the past decades, many researchers have reported that T. fuciformis polysaccharides (TPS) possess various bioactivities, including anti-tumor, immunomodulatory, anti-oxidation, anti-aging, repairing brain memory impairment, anti-inflammatory, hypoglycemic and hypocholesterolemic. The structural characteristic of TPS has also been extensively investigated using advanced modern analytical technologies such as NMR, GC-MS, LC-MS and FT-IR to dissect the structure-activity relationship (SAR) of the TPS biomacromolecule. This article reviews the recent progress in the extraction, purification, structural characterization and applications of TPS.

Hydrazine can be grafted in CPO-27-Mg/MOF-74-Mg to provide an ultrahigh concentration of amine groups on the pore surface, giving an exceptionally high CO2 capture performance, especially at extremely low pressures., Tremendous efforts have been devoted to increasing the CO2 capture performance of porous materials, especially for low CO2 concentration environments. Here, we report that hydrazine can be used as a diamine short enough to functionalize the small-pore metal–organic framework [Mg2(dobdc)] (H4dobdc = 2,5-dihydroxyl-1,4-benzenedicarboxylic acid). By virtue of the ultrahigh concentration of free amine groups (6.01 mmol g–1 or 7.08 mmol cm–3) capable of reversible carbamic acid formation, the new material [Mg2(dobdc)(N2H4)1.8] achieves a series of new records for CO2 capture, such as single-component isotherm uptakes of 3.89 mmol g–1 or 4.58 mmol cm–3 at the atmospheric CO2 concentration of 0.4 mbar at 298 K and 1.04 mmol g–1 or 1.22 mmol cm–3 at 328 K, as well as more than a 4.2 mmol g–1 or 4.9 mmol cm–3 adsorption/desorption working capacity under dynamic mixed-gas conditions with CO2 concentrations similar to those in flue gases and ambient air.

Postsynthetic ion exchange of [Co2(μ-Cl)2(btta)] (MAF-X27-Cl, H2bbta =1H,5H-benzo(1,2-d:4,5-d')bistriazole) possessing open metal sites on its pore surface yields a material [Co2(μ-OH)2(bbta)] (MAF-X27-OH) functionalized by both open metal sites and hydroxide ligands, giving drastically improved electrocatalytic activities for the oxygen evolution reaction (an overpotential of 292 mV at 10.0 mA cm(-2) in 1.0 M KOH solution). Isotope tracing experiments further confirm that the hydroxide ligands are involved in the OER process to provide a low-energy intraframework coupling pathway.

One therapeutic approach for Alzheimer's disease is to inhibit the cleavage of the amyloid precursor protein (APP) by γ-secretase. At the beginning of a series of studies from our laboratories, a series of novel γ-amino alcohols (1) were found to possess γ-secretase inhibitory activity and Notch-sparing effects. A new one-pot synthesis of γ-amino alcohols and the structure-activity relationship (SAR) of these analogs will be discussed.

To simulate the active site cavity structure function and axial coordination of cytochrome P-450 enzymes, mesoporous chitosan(mesp-CTS) was used as a scaffold for a meso-sized cavity to immobilize cobalt tetrakis(p-sulphophenyl)porphyrin chloride(Co TPPS). Immobilization was achieved via an acid–base reaction and axial coordination of the H2N-C group to the Co ion in Co TPPS, thus forming the biomimetic catalyst Co TPPS/mesp-CTS. Several approaches, including scanning electron microscopy (SEM), the Brunauer–Emmett–Teller (BET)technique, Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, thermogravimetric and differential scanning calorimetry (TG-DSC), and X-ray photoelectron spectroscopy (XPS), were used to characterize the grafted catalyst. The catalytic performance of Co TPPS/mesp-CTS in ethylbenzene oxidation without any solvents and additives was investigated. The results showed that only 0.96 × 10 mol of Co TPPS grafted onto mesp-CTS could be recycled three times for 200 mL of ethylbenzene oxidation, with an average yield of 44.6% and selectivity of 68.8%. The highly efficient catalysis can be attributed to promotion by mesp-CTS, including the effect of the mesoporous structure and the axial coordination to the Co ion in Co TPPS. This biomimetic methodology provides a method for clean production of acetophenone via ethylbenzene oxidation.

Wnt/β-catenin signaling is upregulated in triple-negative breast cancer (TNBC) compared to other breast cancer subtypes and normal tissues. Current Wnt/β-catenin inhibitors, such as niclosamide, target the pathway nonspecifically and exhibit poor pharmacokinetics/pharmacodynamics in vivo. Niclosamide targets other pathways, including mTOR, STAT3 and Notch. Novel benzimidazoles have been developed to inhibit Wnt/β-catenin signaling with greater specificity. The compounds SRI33576 and SRI35889 were discovered to produce more cytotoxicity in TNBC cell lines than in noncancerous cells. The agents also downregulated Wnt/β-catenin signaling mediators LRP6, cyclin D1, survivin and nuclear active β-catenin. In addition, SRI33576 did not affect mTOR, STAT3 and Notch signaling in TNBC and noncancerous cells. SRI35889 inhibited mTOR signaling less in noncancerous than in cancerous cells, while not affecting STAT3 and Notch pathways. Compounds SRI32529, SRI35357 and SRI35361 were not selectively cytotoxic against TNBC cell lines compared to MCF10A cells. While SRI32529 inhibited Wnt/β-catenin signaling, the compound also mitigated mTOR, STAT3 and Notch signaling. SRI33576 and SRI35889 were identified as cytotoxic and selective inhibitors of Wnt/β-catenin signaling with therapeutic potential to treat TNBC in vivo.

Tremendous efforts have been devoted to increasing the CO2 capture performance of porous materials, especially for low CO2 concentration environments. Here, we report that hydrazine can be used as a diamine short enough to functionalize the small-pore metal–organic framework [Mg2(dobdc)] (H4dobdc = 2,5-dihydroxyl-1,4-benzenedicarboxylic acid). By virtue of the ultrahigh concentration of free amine groups (6.01 mmol g−1 or 7.08 mmol cm−3) capable of reversible carbamic acid formation, the new material [Mg2(dobdc)(N2H4)1.8] achieves a series of new records for CO2 capture, such as single-component isotherm uptakes of 3.89 mmol g−1 or 4.58 mmol cm−3 at the atmospheric CO2 concentration of 0.4 mbar at 298 K and 1.04 mmol g−1 or 1.22 mmol cm−3 at 328 K, as well as more than a 4.2 mmol g−1 or 4.9 mmol cm−3 adsorption/desorption working capacity under dynamic mixed-gas conditions with CO2 concentrations similar to those in flue gases and ambient air.

Ophiocordyceps sinensis (DCXC) is a well-known traditional Chinese medicine that exhibits various health-promoting effects. However, counterfeits and mimics of DCXC are frequently found in markets. In the present study, we examined the potential of quadrupole time-of-flight mass spectrometry (QTOF–MS) coupled with ultrafast liquid chromatography (UFLC) for use in the authentication of DCXC. Metabolite fingerprinting was obtained and subjected to multivariate statistical analysis. Discrimination of genuine DCXC, its counterfeits, cultured mycelia, and mimics was carried out by principal component analysis–discriminant analysis (PCA–DA). Furthermore, 18 characteristic markers efficiently distinguishing DCXC and its adulterants were selected by creation of profile plots displaying the abundances of markers. Determination of molecular formulae and tentative identification of marker compounds were conducted using elemental formula calculation and online database searches based on accurate MS mass and MS/MS fragmentation information. These results suggested that UFLC–QTOF-based metabolomics has great potential for the rapid detection of DCXC adulteration.

The degradation occurring in soybean oil, camellia oil, and binary blends at five ratios during deep frying of french fries at 180°C for five consecutive days was monitored. The decrease in polyunsaturated and increase in saturated fatty acids during the frying operation was more prominent in soybean oil as compared to the camellia oil and blended oils. Among the frying periods, camellia oil, blend (60:40) and blend (50:50) after frying did not change significantly in the overall fatty acid composition. In addition, results of physicochemical properties of the frying media, namely the free fatty acid, peroxide value, p-anisidine value, total polar components, and color, indicate that camellia oil has the least degradation, while soybean oil has the highest. What is more, these results reveal that increase in oxidative stability is correlated with the increase in camellia oil levels, due to the high content of phenolic compounds and monounsaturated fatty acid. Therefore, the present study clearly indicated that partial replacement of soybean oil with camellia oil can significantly improve frying stability for deep frying of french fries. Practical applications: The results are useful for home cooking, restaurants, or fast foods sellers providing them with newly developed frying stability oils, camellia oil, and camellia/soybean blended oils for deep frying of french fries. Furthermore, discarding time was provided for soybean oil, camellia oil, and their blends when used as media for french fries frying, this suggestion allows preparing safe fried foods for consumers. Total polar compounds of oils during 5 days of usage for deep frying of french fries. Soybean oil (SO); camellia oil (CO); blended oils (soybean oil:camellia oil) SCO1-90:10, SCO2-80:20, SCO3-70:30, SCO4-60:40, SCO5-50:50.

We investigated the effects of a dual-frequency frequency-sweeping ultrasound (DFFSU) treatment on the functional properties and structure of zein. The solubility of ultrasound-treated zein proteins increased slightly but significantly as the treatment time increased. The results showed that the DFFSU treatment had an obvious influence on the mean particle size and the size distribution. A significant (P < 0.05) increase in the size of the particles with respect to time was observed after a sonication time of more than 20 min in zein solutions. Differential scanning calorimetry results showed that sonication alters the thermal behavior of zein. Circular dichroism spectra showed a small increase in the percentage of ordered structure elements within the protein molecule. After 60 min of ultrasonication, the percentage of α-helix structures increased by 0.9%, whereas the percentage of β-sheets and β-turns decreased by 0.5%. Microstructural analyses by scanning electron microscopy showed that several microho...

γ-Secretase is one of two proteases directly involved in the production of the amyloid β-peptide, (Aβ) which is pathogenic in Alzheimer’s disease. Inhibition of γ-secretase to suppress the production of Aβ should not block processing of one of its alternative substrates, Notch1 receptors, as interference with Notch1 signaling leads to severe toxic effects. In the course of our studies to identify γ-secretase inhibitors with selectivity for APP over Notch, 1 [3-(benzyl(isopropyl)amino)-1-(naphthalen-2-yl)propan-1-one] was found to inhibit γ-secretase-mediated Aβ production without interfering with γ-secretase-mediated Notch processing in purified enzyme assays. As 1 is chemically unstable, efforts to increase the stability of this compound led to the identification of 2 [naphthalene-2-carboxylic acid benzyl-isopropyl-amide] which showed similar biological activity to compound 1. Synthesis and evaluation of a series of amide analogs resulted in benzofuranoyl amide analogs that showed promising Notch-sparing γ-secretase inhibitory effects. This class of compounds may serve as a novel lead series for further study in the development of γ-secretase inhibitors.

Nuclear factor-kappaB (NF-kappaB) and Akt are two major cell survival pathways that are often constitutively activated and can be further stimulated by chemotherpeutics in cancer cells. Although individually targeting the NF-kappaB or Akt has been reported to sensitize caner therapy, the effectiveness of concurrent blocking these two pathways for chemosensitizing of cancer cells to genotoxic therapeutics has not been investigated. In the present study, we investigate the activation of the NF-kappaB and Akt pathways by two frontline anticancer drugs cisplatin and etopside in a variety of cancer cell lines. The effects of blocking these two survival pathways individually or concurrently on cisplatin- or etopside-induced cytotoxicity were detected. The results show that cisplatin and etopside activate both NF-kappaB and Akt in cancer cells. Blockade of either of these pathways with chemical inhibitors or siRNA moderately sensitized cancer cells to cisplatin- or etopside-induced cytotoxicity. Strikingly, much more effective potentiation of cytotoxicity to these anticancer drugs was achieved when NF-kappaB and Akt were concurrently blocked. These data suggest that NF-kappaB and Akt cooperatively attenuate therapeutic-induced cytotoxicity and concurrently blocking these pathways is an effective strategy for improving the anticancer efficacy of therapeutics.

The synthesis of perovskite-type oxides using ultrasonic spray combustion (USC) was investigated by adjusting the composition of the precursor solution and the temperature of synthesis and calcination. LaMnO3 was chosen as model perovskite to systematically analyze the effect of USC operating parameters. XRD, IR spectroscopy, TG-TPD, SEM, TEM and BET were used to characterize the samples with respect to phase composition, thermal stability, morphology and surface area. The catalytic properties were evaluated with respect to methane combustion as such materials are potential catalysts in the control of exhaust gases from mobile and stationary sources. Addition of citric acid to the precursor solution and calcination in air appeared to be the crucial parameters to produce spherical hollow particles composed of nano-sized LaMnO3 crystallites (down to 30 nm) with high catalytic activity and durability. Calcination was required in order to remove uncombusted precursors and to improve both the crystallinity of the materials and their catalytic activity. LaFeO3, LaCoO3 and La(M,Pd)O3 (M = Mn, Fe) with pure perovskite-phase were synthesized in a single step under the optimal conditions selected for LaMnO3. Though the order of catalytic activity within the two series of samples (with and without Pd) agreed with reported trends, the production of each single perovskite composition by USC may require further optimization around these synthesis conditions. We demonstrate that USC is a simple, versatile and reliable method with potential application in the one-step synthesis of heterogeneous catalysts.

We report on the chemical actuation of a polypyrrole (PPy) artificial muscle by redox agents in solution without external power supply, such as a battery, connected to the actuator. In particular, hexacyanoferrate and L-ascorbic acid are employed to analyse the strain responses of PPy. The redox agents establish a certain potential at the polymer electrode, which results in a corresponding strain change. The results are in accordance with the strain generated by an external voltage via a potentiostat. We use a bending beam of polyimide/gold/PPy to observe the strain of PPy inside a liquid flow cell. By adding different relative concentrations of the hexacyanoferrate couple to the electrolyte, we achieve a repeatable linear transition in strain without significant hysteresis. Strain changes are induced by redox pairs as well as redox moieties in solution.

Co–Al mixed metal oxide (CoAl-MMO) has been used for surface modification of LiMn 2 O 4 spinel by means of a co-precipitation method in an attempt to improve the electrochemical performance of LiMn 2 O 4 at elevated temperature. The surface modified materials were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDS), Auger electron spectroscopy (AES) and galvanostatic charge–discharge cycling. After heat-treatment at 400 °C, the CoAl-MMO coated LiMn 2 O 4 shows better capacity retention at both 25 °C and 55 °C than the pristine LiMn 2 O 4 . The enhancement in electrochemical performance is mainly attributed to the CoAl-MMO coating layer which has the synergistic effect of cobalt and aluminum oxide species and could block the direct contact between the spinel cathode material and electrolyte resulting in Mn dissolution decrease.

In search for novel lead compounds as γ-secretase inhibitors, analogs of aminopyrido[2,3-d]pyrimidin-7-ones (I) were synthesized and evaluated for inhibitory effects on amyloid –β-peptide production and cleavage of the Notch1 receptor mediated by γ-secretase. Selected pyridopyrimidines, such as 1, 8, 9, 10, 11 and 16 are γ-secretase inhibitors that did not have an effect on Notch1 receptor processing.

A novel method has been employed to synthesize layered LiNi 0.8 Co 0.2 O 2 cathode material by calcination of Ni–Co hydroxide–carbonate precursor prepared by a route involving separate nucleation and aging steps (SNAS) together with LiOH under air atmosphere. Thermogravimetry (TG) and differential thermal analysis (DTA) combined with on-line evolved gas mass spectrometry (EGMS) analysis were employed to study the reaction process. The synthesized material was characterized by means of X-ray diffraction (XRD), laser particle size distribution analysis, field emission scanning electron microscope (FE-SEM) and galvanostatic charge/discharge cycling. The synthesized LiNi 0.8 Co 0.2 O 2 presents a narrow distribution of submicron-sized particles and exhibits a good electrochemical property with initial discharge specific capacity of 194.8 mAh g −1 in the voltage range 2.75–4.5 V (versus Li/Li + ). The novel method for the preparation of submicron-sized LiNi 0.8 Co 0.2 O 2 material has the particular advantage of simple synthesis process and low synthesis cost.

With an increase of benzyl alcohol (BA) content at constant weight ratio of Sodium dodecyl sulfate (SDS) to water, the system capacitance first increases to a maximum in the rod-like micellar region and then decreases in the spherical micellar region. And the differential capacitance remains almost unchanged in the rod-like micellar region and decreases in the spherical micellar region. At constant weight ratio of SDS to BA, neither the system capacitance nor the differential capacitance changes much in the bicontinuous microemulsion (the mixed region of oil in water (O/W) and water in oil (W/O) microemulsion), but both decrease quickly in the oil in water microemulsion (O/W) region with the addition of water content. The variation of capacitance corresponds to the structural transformation of the SDS/BA/H2O system.

Recently, we designed and synthesized a series of chiral ferrocenes and cyclophanes with and without planar chirality. In this review, our own work on the, applications of these ligands in transition-metal catalyzed enantioselective carbon–carbon bond forming reactions, including asymmetric allylic substitution reactions of ketone imino esters, enolates of simple ketone and mono substituted allyl substrates, intermolecular Heck reaction of dihydrofuran and pyrrol, addition reactions of diethylzinc to carbonyl derivatives are presented with emphasis on the regio- and enantioselectivities of the reactions. The role of planar chirality of ferrocenes and cyclophanes as well as some of their structural features influence the reactivity and enantioselectivity in asymmetric catalysis are also discussed.

Synthetic approaches to the total synthesis of plakortone B, as well as diastereoselective nucleophilic additions to furyl aldehyde and furyl sulfonylimine employing chiral 3-boronates as auxiliary are presented.

The first example of a direct aldehyde–ketone coupling using the secondary amine piperidine as base in the presence of MgI2 to generate high selectivity of anti-aldol products from unmodified ethyl ketones in high yield is reported. The coupling reactions were carried out in a one-pot reaction by mixing four reaction components at room temperature. In the case of unsymmetrical ketones, addition was made to the less hindered α-side.

The first time steroselective synthesis of ( Z )-β-bromo Baylis–Hillman ketones has been achieved using a one-pot three-component reaction. The new system uses MgBr 2 as both the Lewis acidic promoter and the bromine source for the Michael-type addition with α,β-acetylenic ketones to form an active β-bromo allenolate intermediate, which in turn attacks various aldehydes to afford β-bromo Baylis–Hillman adducts in good yields and Z -selectivity.

Low-temperature crystal structures of three pyrrolediones (3-5) and a furandione (9) were obtained and compared to structurally related compounds that cannot undergo decarbonylation. Systematic trends in bond lengths and angles are consistent with distortions along the reaction coordinate, in accord with the structure correlation principle of Dunitz. Since the pyrroledione and furandione rings in 3-5 and 9 are planar, these ground-state geometries prefigure the calculated planar, pseudopericyclic transition states.

The efficient and highly stereoselective syntheses of a variety of (Z)-configured, substituted α-(hydroxymethyl)-β-iodo-acrylates from prop-2-ynoate and various aldehydes was achieved. The synthetic protocol involves a simple one-pot coupling reaction under mild conditions, promoted by MgI2, which serves both as a Lewis acid and iodine source for a BaylisHillman-type reaction. All adducts were generated in good-to-excellent yields, the (Z)-isomers being formed in high selectivity (>98%). The conversion of methyl prop-2-ynoate into an active ‘β-iodo allenolate’ intermediate, which then nucleophilically attacks an aldehyde, is proposed as a plausible reaction mechanism.

The adsorbent derived from sewage sludge through chemical pyrolysis has been used for the adsorption of Cd 2+ and Ni 2+ from aqueous solution. Parameters such as the agitation time, metal ion concentration, adsorbent dosage and pH were studied. The adsorption data fit well with the Langmuir and Freundlich isotherm models. The capacity of adsorption calculated from the Langmuir isotherm was 16, 9 mg/g for Cd 2+ and Ni 2+ , respectively at the initial pH of 5.8 at 25 °C. And the agitation time of 60 min was necessary for the adsorption to reach equilibrium, the optimum pH value in the range of 5.5–6.0. Desorption studies were performed with dilute hydrochloric acid. Quantitative recovery of the metal ion is possible. The mechanism of adsorption seems to be ion exchange. As the sewage sludge is discarded as waste from wastewater treatment processing, the adsorbent derived from sewage sludge is expected to be an economical product for metal ion remediation from water and wastewater.

The sewage sludge was used to produce adsorbent by controlling the pyrolytic and chemical conditions. Using the adsorbent derived from sewage sludge to adsorb the low concentration SO2 in fixed bed system, the effects of the metallic derivatives on characteristics of the adsorbent were investigated at different compositions of the gaseous mixtures. The results show that when the mass fraction of vanadium reaches 0.5% and the mass fraction of iron, calcium, copper, nickel reach approximately 0.9%, under the condition that the adsorption mixture contains 0.12%SO2, 3%O2 and 10% water vapor, the maximum adsorption capacity of SO2 can be obtained to be 128, 109, 90, 82, 78 mg · g−1, respectively. So the metallic derivatives fixed onto adsorbent derived from sewage sludge especially vanadium have great effects on of the sorption characteristics of the adsorbent with respect to SO2.

An asymmetric synthesis of β-iodo-α-(hydroxyalkyl)acrylates has been developed involving conjugate addition of I− to menthyl propiolates to give β-iodo allenolate intermediates which undergo 1,2-addition to form β-iodo Baylis–Hillman products. Modest diastereoselectivities (37–58% de) and excellent yields (80–87%) were obtained when (1R,2S,5R)-(−)-menthol was used as a chiral auxiliary. The two diastereoisomers of the product were separated by silica gel chromatography to give diastereomerically pure products.

The corrosive properties of nickel are studied by measuring the weight loss, the voltammetry and the impedance in SDS/C2H5OH/H2O/HCl system and SDS/n-C4H9OH/H2O/HCl system, respectively. The inhibition efficiency of surfactant SDS for nickel increases with the increase of SDS content. The corrosion rate of nickel first increases up to the maximum and then decreases with the increase of alcohol content. The addition of butanol and ethanol can increase the corrosion rate of nickel in HCl(aq) solution, which means the corrosion rate can be adjusted by ethanol even though the effect of ethanol on the inhibition efficiency is less than that of n-butanol. The orders of the corrosion rates, the electrochemical corrosion rate constant and the electrochemical exchange current of nickel corrosion in different media are HCl(aq)>surfactant+alcohol+HCl(aq)>surfactant+HCl(aq)>surfactant+alcohol(aq)>surfactant(aq).

An efficient one-pot, three-component coupling reaction for the synthesis of β-iodo-α-(hydroxyalkyl) acrylates has been developed. As the iodine source as well as the Lewis acid mediator, diethyl aluminium iodide undergoes a Michael-type addition with methyl propynoate to form an active β-iodo allenolate intermediate, which in turn attacks various aldehydes or ketones to afford β-iodo Baylis–Hillman adducts in excellent yields with high Z-selectivity.

The FeCl(3)-PPh(3) complex was found to effectively catalyze the electrophilic diamination reaction of electron-deficient alkenes. Improvements on yields and stereoselectivity have been achieved for both alpha,beta-unsaturated carboxylic esters and ketones. Under the new catalytic system, alpha,beta-unsaturated carboxylic esters were found to be superior to their ketone counterparts, which is opposite to the previous (C(3)F(7)CO(2))(2)Rh](2)-catalyzed diamination. The reaction employs readily available N,N-dichloro-p-toluenesulfonamide (TsNCl(2)) and acetonitrile as the nitrogen sources and is very easy to perform at room temperature without the special protection of inert gases. The resulting diamino products belong to imidazolidine analogue and can further strengthen the importance of the new reaction. Modest to good yields (52-84%) and high regio- and stereoselectivity have been achieved for 10 examples.

Highly stereoselective synthesis of (E)-β-bromo Baylis-Hillman ketones has been achieved using a three-component X–C/C–C formation reaction. The synthesis involves the Michael-type addition of TiBr4 to α,β-acetylenic ketones without using any bases and carbonyl coupling with aldehydes. Modest yields (50–65%) and complete E/Z geometric selectivity have been realized for 10 examples.

a,b-Ethyl thioacrylate was difuctionalized by a tandem X-C/C=C bond formation reaction. The new system uses Ti (IV) halide as both the Lewis acidic promoter and the halogen source for the Michael-type addition onto the thioacrylate. The titanium enolate species resulting from Michael-type addition react with aldehydes followed by dehydration to afford trisubstituted olefin products. Complete geometric selectivity (>95%) and up to 72% yield have been obtained for 7 examples.

The mechanical properties of AISI 4140 steel shaft with a diameter larger than 200 mm are difficult to meet the requirements and cracking occurs easily in water quenching, due to insufficient cooling ability of oil quenching. A new technology, named alternately timed quenching (ATQ), using water and air in turn as quenching media instead of oil or polymer aqueous solution, is applied to quench the large-scale AISI 4140 steel shaft. Two ATQ processes are determined with the aid of computer simulation first and the corresponding experiments are carried out consequently. The results show that the proposed technology can significantly reduce the surface cracking tendency and improve the mechanical properties in practical production of such large-scale shaft forgings.

A substoichiometric amount of titanium tetrachloride was found to be effective to promote and participate in the tandem α-hydroxyalkylation/β-chlorination of α,β-acetylenic ketones in the presence of (n-Bu)4NI. This method provides the concise synthesis of (E)-β-halo Baylis–Hillman adducts. No β-iodo products were detected when using this combination of halogen sources. The reaction process involves 1,4-addition of chloro anion released from TiCl4 onto α,β-acetylenic ketones to give TiCl3–allenolate intermediates followed by the titanium Lewis acid-promoted carbonyl addition. Modest to good yields (53–77%) and excellent E/Z stereoselectivity (>95%) have been obtained for 10 examples.

A three-component electrophilic reaction transforms olefins into imidazoline and diamine derivatives. Rhodium(II) heptafluorobutyrate dimer (2 mol %) was utilized as the catalyst and N,N-dichloro-p-toluenesulfonamide (TsNCl2 ) and acetonitrile as the nitrogen sources. Modest to good yields (45-82 %) and high regio- and stereoselectivity were achieved.

N-Chloro-N-sodium-sulfonamide was found to react with olefins in the presence of copper catalyst to give vicinal haloamine derivatives instead of aziridines. The resulting regio and stereochemistry indicates that this unexpected reaction could proceed through the formation of unprecedented N-chloro-N-copper-2-nitrobenzenesulfonyl aziridinium intermediates, which can increase the successful chance to render the asymmetric version of the aminohalogenation reaction. In addition, this finding provides a more convenient protocol by the use of solely pure NsNClNa for the aminohalogenation reaction as compared to the mixed nitrogen and chlorine sources consisting of NsNCl2 and NsNHNa as previously reported by us. Two new simple olefin substrates, trans-stilbene and styrene, were also found to be effective for this new reaction system.

Transition metal–ligand complex-catalyzed regio- and stereoselective aminohalogenation of cinnamic esters has been developed using p-TsNCl2 as the nitrogen and chlorine sources. Dichloro-(1,10-phenanthroline)-palladium (II) as the catalyst can be handled very conveniently due to its property of less hygroscopic as compared with other aminohalogenation catalysts. The reaction is suggested to proceed through the mechanism involving N-tosyl N-chloro aziridinium intermediate. Eight examples are presented with modest to good yields (56–82%) and excellent stereoselectivity (>10:1).

A series of novel planar chiral N,O-[2,2]paracyclophane ligands were synthesised and applied as catalysts in the enantioselective addition of diethylzinc to aldehydes. The results indicate that the planar chirality of [2,2]paracyclophane, not the central chirality of the oxazoline, is the dominant stereocontrolling element.

The asymmetric catalytic aldol reaction of silyl allenolates with aldehydes has been achieved by using N-C(3)F(7)CO oxazaborolidine as the catalyst. The fluoroacyl group of the catalyst was found to be crucial for control of enantioselectivity. The reaction provides the first enantioselective approach to beta-halo Baylis-Hillman-type adducts.

New chiral N,S-ligands with oxazoline and thiophenyl sub-stituents at benzene ring and benzylic postition have been pre-pared and applied in palladium-catalyzed asymmetric allylic alkylation reaction to provide the product with high yield and entantioselectivity (82%-93%)ee.

Tandem diamination of cinnamic esters provides a new approach to anti alkyl Nα-(2-Ns), Nβ-Ac diaminophenylpropionates. The new reaction proceeds to completion within 3 hours at room temperature using N,N-dichloro-2-nitrobenzenesulfonamide (2-NsNCl2) as the nitrogen source in acetonitrile, which is also involved in the reaction process. Seven diamine derivatives have been obtained with good yields and stereoselectivity.

New regio- and stereoselective aminohalogenation of cinnamic esters has been developed using the combination of 2-NsNCl(2)/2-NsNHNa as the nitrogen and chlorine sources and copper(I) triflate as the catalyst. The new procedure provides an efficient synthesis of anti-alkyl 3-chloro-2-(o-nitrobenzenesulfonamido)-3-phenylpropionate derivatives. Nine examples are presented with good yields (62-82%) and stereoselectivity ((5:1)-(30:1)).

A highly stereoselective method for the synthesis of (E)-β-halogeno Baylis–Hillman adducts has been developed. The new method involves a tandem α-hydroxyalkylation/β-chlorination of α,β-acetylenic ketones by using TiCl4 as the chlorine source for α,β-conjugate addition, and concurrently as the Lewis acid promoter for the carbonyl addition. The new system tolerates a broad scope of reactants in which aliphatic and aromatic α-acetylenic ketones can be subjected to the conjugate addition. Both aliphatic and aromatic aldehydes can also be employed as electrophilic acceptors. Good yields (61–88%) and high E/Z stereoselectivity have been obtained for the nine examples which were examined, only in one case was E/Z selectivity of 17/1 observed and the two individual isomers are separable via flash column chromatography.

TiCl4-Mediated Baylis–Hillman and aldol reactions were developed without the direct use of a Lewis base. These processes involve the conjugate addition of TiCl4 to α,β-unsaturated substrates followed by carbonyl coupling. Baylis–Hillman olefins were obtained when α,β-unsaturated ketones were employed as the substrates, whereas β-halogenated aldol products were generated with an α,β-unsaturated N-acyl benzoxalinone as the Michael-type acceptor.

An efficient deprotection of N - p -toluenesulfinyl group of β-branched Baylis–Hillman adducts has been developed by using Amberlite IR-120 (plus) ion-exchange resin in methanol solution at room temperature. Good to quantitative yields have been obtained for six examples. No racemization was detected under the mild conditions. This new method provides a simultaneous deprotection/purification, which has the great advantage over the solution phase deprotection technique of simplicity of work-up.

A new mild procedure has been developed for the synthesis of cis β-bromostyrene analogs with complete Z/E selectivity and good to excellent yields (58.4 - 90.9%). The process involves carboxyl-halo-elimination of cinnamic acid dibromides by using triethylamine in N,N-dimethylformamide at room temperature. A one-pot procedure has also been described for the direct transformation of cinnamic acids to β-bromostyrenes.