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The reaction of diaryliodonium salts with difluoromethyltriflate in the presence of TBAT and CuTC gave the corresponding trifluoromethylated arenes in moderate yields. Compared to other difluorocarbene-derived trifluoromethylation reactions, the current one proceeded at mild reaction conditions (room temperature) within short reaction time (5 min).

Two new congruent-melting alkali metal diphosphates, Rb2CdP2O7 and Cs2CdP2O7, were synthesized by conventional solid-state reactions. Single-crystal X-ray structural analyses showed that M2CdP2O7 (M = Rb, Cs) feature two-dimensional [CdP2O7](2-) layers that are composed of CdO5 pyramids and P2O7 dimers. The Rb+ and Cs+ cations ions fill the interlayers. The flexible P2O7 dimers could be bent and distorted if the Cs+ ion was substituted by the Rb+ ion, which led to crystallization of the Rb2CdP2O7 compound in the lower symmetry monoclinic space group P2(1)/c (No. 14) and crystallization of the Cs2CdP2O7 compound in the high-symmetry orthorhombic space group Pnma (No. 53). Thermal analyses showed that the two compounds melt congruently and that the melting point of Rb2CdP2O7 compound is lower than that of the Cs2CdP2O7 compound owing to distortion of the P2O7 dimers. IR spectroscopy and UV/Vis-near-IR diffuse reflectance spectroscopy were performed on the reported compounds.

Cs3Pb2(CO3)3I (I) is prepared by hydrothermal reaction of Cs2CO3, PbI2, Rb2CO3, and NaOH (autoclave, 200 °C, 3 d; cooling to 25 °C at a rate of 3 °C/h).

Single crystals of Ba2B6O11 are prepared by spontaneous crystallization from a melt of BaF2, H3BO3, and PbO in the molar ratio of 5:25:3 (950 °C, 5 d; cooling to 200 °C at a rate of 0.02 °C/h).

Highly conductive, crystalline, polymer electrolytes, β-cyclodextrin (β-CD)-polyethylene oxide (PEO)/LiAsF6 and β-CD-PEO/NaAsF6 , were prepared through supramolecular self-assembly of PEO, β-CD, and LiAsF6 /NaAsF6 . The assembled β-CDs form nanochannels in which the PEO/X(+) (X=Li, Na) complexes are confined. The nanochannels provide a pathway for directional motion of the alkali metal ions and, at the same time, separate the cations and the anions by size exclusion.

Single crystals of Na3B4O7X (X: Cl, Br) are grown by spontaneous crystallization from a 1:1:3 molar mixture of Na2CO3, NaCl (NaBr), and H3BO3 (Pt crucible, 750 °C, 12 h;.

The new title compound is hydrothermally synthesized by reaction of Ni(OAc)2, V2O5, H3BO3, and en in H2O (autoclave, 200 °C, 3 d, 92% yield).

isolation and structure elucidation of three new diterpenes, 14-dehydroxy-12,16-dihydrocaesaldekarin L (I), 1-deacetyl-12-ethoxyneocaesalpin N (IIa), and 1-deacetylneocaesalpin N (Ib), along with two known cassane-type diterpenes

The new title compounds are prepared by solid state reactions of stoichiometric mixtures of MO3 (M: Mo, W), Rb2CO3, and Na2CO3 (673 K for 10 h and 843 K for 48 h).

Single crystals of the title compounds are prepared from mixtures of M2CO3 (M: Rb, Cs), CdO, and H3BO3 at ratios of 1:1:10 (Pt crucible, 300, 600, and 850 °C, 12 h each).

Millimeter-sized single crystals of the title compound are obtained from a melt of Li2CO3, Na2CO3, BaCO3, PbO, and H3BO3 in the molar ratio of 7:5.5:3.5:20 (Pt crucible, 800 °C, 10 h).

by Huai-Qiong Chena), Jian-He Wei*a), Jun-Shan Yanga), Zheng Zhanga), Yun Yangb), Zhi-Hui Gaoa), Chun Suia), and Bao Gongb) a) Institute of Medicinal Plant Development (Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education), Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, P. R. China (phone: þ86-10-62818841; e-mail: wjianh@263.net) b) Hainan Branch Institute of Medicinal Plant (Hainan Provincial Key Laboratory of Resources Conservation and Development of Southern Medicine), Chinese Academy of Medical Sciences & Peking Union Medical College, Wanning 571533, P. R. China

A new compound, Pb2BO3F, has been grown by high temperature solution method from the PbO-PbF2-B2O3 system for the first time. The crystal structure of this compound has been identified by single crystal X-ray diffraction analysis. It crystallizes in the hexagonal system, space group P6(3)/m (No. 176) with unit-cell parameters a =7.2460(3) angstrom, c=14.5521(17) angstrom, Z=6, V=661.69(9) angstrom(3). Its structure was solved by the direct methods and refined to R-1=0.0163 and wR(2)=0.0367. The structure of Pb2BO3F consists of the distorted PbO3F2 groups and BO3 triangles, which are all symmetric with each other in the gestalt structure to the extent that the Pb2BO3F compound crystallizes in the symmetric space group. The powder X-ray diffraction pattern of the Pb2BO3F has been measured. The BO3 functional groups presented in the sample were identified by FTIR spectrum. The DTA curve of Pb2BO3F suggests that Pb2BO3F melts congruently at 448 degrees C.

The novel title compound is synthesized by solid state reaction of a stoichiometric mixture of H3BO3, CdO, and Ba(NO3)2 (800 °C, 60 h).

The title compound, a new nonlinear optical material, is prepared by solid state reaction of a stoichiometric mixture of Li2CO3, Cs2CO3, and H3BO3 at 560 °C (48 h).

3-(Tri-n-butylstannyl)-4-lithiofuran 2, obtained through tin–lithium exchange from 3,4-bis(tri-n-butylstannyl)furan 1, reacts regiospecifically with various electrophiles to give monosubstituted stannylfurans, which are converted into unsymmetrical 3,4-disubstituted furans utilising Stille's palladium-catalysed coupling reactions.

This Account describes how stereochemical ideas focused on chirality have been directed widely across polymer science allowing experiments that could not be conducted on small molecules and leading to new insights and new kinds of materials. In one approach, a helical polymer was studied, and it was discovered how the chiral information necessary to choose helical sense is greatly amplified. In another approach, the racemization kinetics of atropisomers were used to characterize the restrictions to motion associated with a polyelectrolyte that forms clusters around hydrophobic groups in water and in an entirely different system, the glassy state formed by polymers.

Chemical investigation of Feces Trogopterus (Trogopterus xanthipes) has led to the isolation of three new lipids, including two new cerebrosides, 1-O-(β-D-glucopyranosyloxy)-(2S,3S,4R,6E)-2-[(2'R)-2'-hydroxyheptadecanoylamino]-8-heptadecene-3,4-diol (1) and 1-0-(β-D- glucopyranosyloxy)-(2S,3S,4R,6E)-2-[(2'R)-2'-hydroxy-heptadecanoylamino]-8-nonadecene-3,4-diol (2), and one new fatty acid ester, bis(2,3-dihydoxypropyl)-tetracosanedioate (3). Their structures were elucidated by chemical and spectral means. This is the first report on the occurrence of cerebroside and fatty diacid diester in Feces Trogopterus.

A highly efficient nickel-catalyzed asymmetric alkylative coupling of alkynes, aldehydes, and dimethylzinc has been realized by using bulky spirobiindane phosphoramidite ligands, affording allylic alcohols with a tetrasubstituted olefin functionality in high yields, high regioselectivities, and excellent enantioselectivities.

2-Azido-3-arylacrylates react with α-diazocarbonyl compounds and triphenylphosphine to furnish isoquinolines in 60−92% yields. The tandem process involves a Wolff rearrangement, an aza-Wittig reaction, and an electrocyclic ring closure. The procedure is efficient, rapid, and general, and the substrates are readily available.

A one-pot cascade approach to 4-alkylidene-β-lactams and N,N′-diarylamidines from aryl azides and aryloxyacetyl chlorides has been developed. The chemical outcome of the reaction can be controlled selectively by an appropriate choice of the stoichiometric ratio of different substrates and reagents. The products should find use in pharmaceutical discovery, especially in the development of new antimicrobial agents against multidrug-resistant pathogens.

Silylated Ti-grafted hexagonal mesoporous silica (HMS) catalyst was prepared by the chemical vapor deposition (CVD) using TiCl 4 as titanium source and hexamethyldisilazane (HMDSZ) as silylating agent. The samples were characterized by XRD, N 2 -adsorption, FTIR, 29 Si NMR, DR UV–vis, and evaluated by epoxidation of styrene, propylene, cyclohexene, and 1-hexene with cumene hydroperoxide (CHP) as oxidant, respectively. It is revealed that the catalyst possesses typical mesoporous structure, high hydrophobicity and highly dispersed tetracoordinated titanium sites and hence exhibits excellent performance in epoxidation of olefins.

A novel, general, and mild method is described to prepare 2,2-diphenyl-1,3-diones with benzyne using CuBr and trichloroacetic acid as the catalyst.

The progress on the combustion synthesis of Si3N4 powders during the past decades was summarized with the emphasis on the recently developed mechano-chemically activated combustion synthesis (MACS) method. The effects of processing parameters such as the addition of diluent and ammonium salts into the green mixtures, the variation of nitrogen pressure as well as the mechanical activation treatment on the degree of Si to α-Si3N4 conversion was evaluated. The combination of mechanical activation and chemical stimulation was effective in enhancing the reactivity of Si powder reactants, which was responsible for the extension of the minimum nitrogen pressure normally required for the combustion synthesis of Si3N4. This breakthrough indicates that nitriding combustion of silicon in pressurized nitrogen could be promoted by activating the solid reactants instead of by increasing the pre-exerted nitrogen pressure. The MACS process was successfully applied to the industrial production of Si3N4 powders, the regularities for the large-scale synthesis were reported, and the as-synthesized Si3N4 powder products were systematically characterized.

Aromatic aldehydes reacted with anilines and benzenediazonium-2-carboxylate to afford 6-aryl-phenanthridines. The reaction furnishes a rapid and direct construction of substituted phenanthridine rings from readily available starting materials via a one-pot cascade process.

A Zn(OTf) 2 -catalyzed cascade reaction of anilines with aromatic aldehydes and carbonyl compounds was described. This one-pot three-component reaction afforded the corresponding β-amino carbonyl compounds, β-amino esters, and β-amino ketones in good to excellent yields. The reaction was also applied for the liquid-phase synthesis of β-amino carbonyl compound library using PEG as a support.

A rapid and efficient synthesis of substituted phthalates via microwave‐promoted Beller's reaction of aldehydes, amides, and dimethyl acetylenedicarboxylate is described. This one‐pot, multicomponent reaction was performed under acetic anhydride–free and solvent‐free conditions.

Two new organocatalysts derived from l -proline and a novel chiral spiro diamine bearing a C 2 symmetric backbone, were introduced for an asymmetric aldol reaction in moderate to good asymmetric induction in up to 76% ee and high yields.

Four novel cobalt(III) complexes were found to have high catalytic activities and excellent selectivities in the oxidation of ethylbenzene to acetophenone using O2 as oxidant without need of solvent.