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Herein, a Pd/Cu bimetallic-catalyzed direct C-H heteroarylation of pyridines via the traceless protecting group strategy is described. A series of N -methyl-activated pyridines and 1-methylindoles are coupled with high regioselectivity to produce the corresponding 3-(pyridin-2-yl)indoles in moderate to good yields, wherein related electron-rich heterocycles (e.g., indole, 1-methylpyrrole, benzofuran, benzo[ b ]thiophene) are also applicable. Streamlined operation, good functional group tolerance, and late-stage modifications make this twofold C-H activation protocol an attractive route for the synthesis of 3-(pyridin-2-yl)indole derivatives.

The introduction of amines onto aromatics without metal catalysts and chemical oxidants is synthetically challenging. Herein, we report the first example of an electrochemical cross-dehydrogenative aromatization (ECDA) reaction of saturated cyclohexanones and amines to construct anilines without additional metal catalysts and chemical oxidants. This reaction exhibits a broad scope of cyclohexanones including heterocyclic ketones, affording a variety of aromatic amines with various functionalities, and shows great potential in the synthesis of biologically active compounds.

The NaIO 4 -mediated sequential iodination/amidation reaction of N -alkyl quinolinium iodide salts has been first developed. This cascade process provides an efficient way to rapidly synthesize 3-iodo- N -alkyl quinolinones with high regioselectivity and good functional group tolerance. This protocol was also amenable to the isoquinolinium salts, thus providing a complementary method for preparing the 4-iodo- N -alkyl isoquinolinones.

An efficient Pd-catalyzed arylation of alkylpyridine based on the pyridinium activation strategy has been developed for synthesis of mixed aryl alkylpyridines. It was found that (1) the N -methyl group in the pyridinium salts acted as a transient activator and could be automatically departed after the reaction, (2) CuBr was an indispensable additive for achieving the C 6 -selective arylation, (3) the α-branched alkyl chain on the alkylpyridine greatly increased the yield of the product. Deuterium labelling experiment revealed that in the case of the α-branched alkylpyridine, the presence of CuBr completely inhibited the H/D exchange at the benzylic position and thus enabled the selective arylation at the C 6 position. This protocol demonstrates a broad substrate scope, and with respect to both the aryl iodides and the α-branched alkylpyridine, the desired mixed aryl alkylpyridines were obtained in generally good to excellent yields.

The hydroformylation of long chain alkenes catalyzed by a water soluble Rh/TPPTS complex (TPPTS: sodium salt of sulfonated triphenylphosphine) in methanol was investigated. The mixture of rhodium precursor HRh(CO)(TPPTS) 3 , ligand TPPTS, methanol and a long chain alkene becomes a single phase under reaction conditions, which make the hydroformylation reaction proceed homogeneously. Both the conversion of long chain alkene and the selectivity to aldehydes (including the aldehydes forming methylacetals) could reach up to 97.8% and 97.6%, respectively, with 3323 h -1 of TOF (TOF: turnover frequency is defined as the moles of converted alkene per mole of Rh per hour). After the solvent methanol was removed under the reaction temperature, two phases were formed automatically. The colourless product phase could be efficiently separated from the precipitate rhodium catalyst phase by centrifuge. The catalyst was reused for five times without obvious loss of rhodium and the catalytic activity. The rhodium leaching in product mixture was less than 0.03% of the total rhodium., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Herein, an efficient and green method for the selective synthesis of tertiary amines has been developed that involves iridium-catalyzed alkylation of various primary amines with aromatic or aliphatic alcohols. Notably, the catalytic protocol enables this transformation in the absence of additional base and solvent. Furthermore, the alkylation of nitrobenzene with primary alcohol to tertiary amine has also been achieved by the same catalytic system. Deuterium-labeling experiments and a series of control experiments were conducted, and the results suggested that an intermolecular borrowing hydrogen pathway might exist in the alkylation process.

The first Pd-catalyzed multicomponent reaction of aryl iodides, alkenyl bromides, and strained alkenes has been developed, which allowed us to synthesize a variety of multisubsituted olefins in yields of 45-96% with excellent stereoselectivity. The configuration of the product was controlled by the configuration of the alkenyl bromides. Moreover, this practical methodology employing readily available substrates was found to be tolerant to a wide range of functional groups. Fifty six examples of highly stereoselective tri- or tetrasubstituted olefins have been successfully synthesized via this methodology. Most of the synthesized tetrasubstituted olefins are good aggregation-induced emission (AIE) luminogens.

Although gastric tumors have overlapping radiologic appearances, some unusual tumors may present specific imaging features. Using multidetector computed tomography (MDCT), with water as a negative oral contrast agent and intravenous contrast medium, can provide critical information for the diagnosis of gastric diseases. In addition, MDCT can evaluate the involvement of the gastric wall and extragastric extent of the disease, as compared with gastroenteroscopy and double-contrast upper gastrointestinal study. Regarding lesion location and size, enhancing and growth patterns, presence of calcification or fat, and involvement of the gastric wall and adjacent structures, CT may provide useful information. In this review article, we review the relevant literature and discuss the CT features and the histopathologic findings of different types of gastric lesions. The lesions are divided into benign (glomus tumors, schwannomas, leiomyomas, and lipomas), malignant (gastrointestinal stromal tumors, mucinous carcinomas, lymphomas, and carcinoid tumors), and tumor-like lesions (ectopic pancreas and bezoar). Familiarity with imaging appearances and pathologic findings can help physicians make an accurate diagnosis., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflict of interest or source of external funding.