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1.
《中国化学》2017,35(9):1337-1337
The cover picture shows a new protocol for the NiCl2 ‐catalyzed cross‐electrophile coupling of aryl bromides with pyrimidin‐2‐yl tosylates to give the corresponding C2 ‐arylation pyrimidine derivatives. This study provides an improvement over previous methods by using pyrimidin‐2‐yl tosylates instead of halides as coupling partners that are stable and easily available. More details are discussed in the article by Wang et al. on page 1366–1370.

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2.
《中国化学》2018,36(2):172-172
The back cover picture shows an efficient dual enantioselective synthesis of 1‐substituted 1,2,3,4‐tetrahydroisoquinoline, which was realized through iridium‐catalyzed hydrogenation of 1‐substituted 3,4‐dihydroisoquinolines. Only tuning the amount of N‐bromosuccinimide, this reaction promoted by (R)‐BINAP is able to furnish both enantiomers of products up to 89% ee (S) and 98% ee (R), respectively. Dual activation role of N‐bromosuccinimide is proposed to be responsible for the reversal of enantioselectivity under two hydrogenation conditions. More details are discussed in the article by Zhou et al. on page 139–142.

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3.
《中国化学》2017,35(9):1338-1338
The inside cover picture shows secondary and tertiary amines, which are important intermediates in organic synthesis for the preparation of natural products, pharmaceutical and agronomical compounds. The direct reductive amination of aldehydes and ketones represents a powerful tool for the preparation of secondary and tertiary amines. Here, direct and general reductive amination of aldehydes and ketones with amines and nitroaromatics was presented under H2 using recyclable iridium catalysts, and lots of secondary and tertiary amines were produced in high yields. Moreover, the heterogeneous iridium catalysts Ir@NC(600‐2h) can be reused several times without evident deactivation. More details are discussed in the article by Huang et al. on page 1371–1377.

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4.
《中国化学》2018,36(8):673-673
The cover picture shows Two efficient intermolecular oxidative coupling reactions of (Z)‐enamines with isocyanides via palladium catalysis have been developed. In these transformations, the β‐C(sp2)‐H and/or C = C bond were cut off selectively by using different anionic ligands, leading to controllable chemodivergent and stereoselective construction of a wide range of (E)β‐carbamoylenamine derivatives with intramolecular hydrogen bonds. More details are discussed in the article by Jiang et al. on page 712–715.

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5.
《中国化学》2018,36(4):265-265
The cover picture shows a simple milling‐mediated solid reduction method for fabricating of ultrafine gold catalysts. By solid grinding of the N‐modified SiO2 supported Au precursors with NaBH4, subnanometer‐sized clusters and isolated Au atoms can be facilely obtained by tuning the metal loading. This method establishes a good basis for fundamental understanding the size effect of Au in the hydrogenation of CO2 to formate, and provides a general methodology for supported nano‐catalyst preparation. More details are discussed in the article by Huang et al. on page 329–332.

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6.
《中国化学》2018,36(2):86-86
The inside cover picture shows an outline of significant advances on exhaust gas e.g. sustainable CO2 recycling into urethanes via effective and renewable silver catalysis. Through one‐pot two‐step stepwise reaction of propargylic alcohols, CO2, and various amines, a wide range of urethanes are obtained in excellent yields and selectivity together with unprecedented high TON and TOF value under mild conditions. Here, robust catalyst is compared to Magician's hand for its versatility in organic synthesis, and the picture indicates the meanings of greenness and transformation. More details are discussed in the article by Zhang et al. on page 147–152.

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7.
《中国化学》2018,36(5):373-373
The cover picture shows the complexity of the reaction mechanism of zeolites catalyzed methanol‐to‐olefins (MTO) conversion. The MTO process plays a vital role in the production of light olefins from nonpetroleum resources. Despite of the successful industrialization of the MTO process in China, the detailed reaction mechanism is not yet well understood. The theoretical studies on the MTO hydrocarbon pool mechanism by the Group of Xie are summarized in the Chemistry Author Up Close by Xie et al. on page 381–386.

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8.
《中国化学》2018,36(10):980-980
The back cover picture shows As two important heterocyclic active groups, oxadiazole and thiadiazole are used to develop new pesticide with high efficiency and broad spectrum of biological activities. On the basis of our previous works, forty one novel 1,3,4‐oxadiazole/thiadiazole thioether derivatives were synthesized and their nematicidal activities against Tylenchulus semipenetrans were evaluated. And compound 33 was designed by using the CoMFA and CoMSIA models, which exhibited excellent nematicidal acivity in vitro. More details are discussed in the article by Song et al. on page 939‐944.

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9.
《中国化学》2018,36(7):565-565
The cover picture shows a protocol of an anionic copolymerization of carbonyl sulfide (COS) with epoxides via alkali metal alkoxides. COS is an analogue of carbon dioxide (CO2), and can be converted to CO2 via the carbonic anhydride enzymes widely existing in nature. It causes acid rain, ozonosphere damage and haze by a series of photochemical reactions. Very simple and low‐cost alkali metal alkoxides are shown as effective catalysts, affording highly transparent poly(monothiocarbonate)s with 100% alternating degree, >99% tail‐to‐head (T‐H) content, high number‐average molecular weights with narrow molecular weight distributions. This is an environment‐friendly and atom‐economic process for making sulfur‐containing polymers. More details are discussed in the article by Zhang et al. on page 625–629.

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10.
《中国化学》2018,36(8):674-674
The inside cover picture shows Metal‐organic layer (MOL), the two‐dimensional analog of metal‐organic framework (MOF), is a new member of two‐dimensional materials. This tutorial review summarizes current synthetic approaches for MOL preparation. More details are discussed in the article by Wang et al. on page 754–764.

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11.
《中国化学》2017,35(9):1477-1477
The inside back cover picture shows a simple and efficient Cu(II )‐catalyzed ligand‐free oxidation of diarylmethanes and secondary alcohols using 70% TBHP in water. A series of diarylmethanes were directly oxidized into diaryl ketones in 67%–98% yields. Additionally, various secondary alcohols were also transformed into the desired products in 48%–98% yields. Importantly, the catalytic system in the absence of any organic solvent, surfactant, or phase transfer agent, had a wide substrate scope and a high tolerance for various functional groups. More details are discussed in the article by Liu et al. on page 1391–1395.

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12.
《中国化学》2018,36(3):173-173
The control of stereoselectivity in radical reactions is of great importance, but remains a formidable challenge. The cover picture shows that the enantiomerically pure compounds can be prepared in radical transformations using chiral transition metal complexes as catalysts. Recent advances are summarized in the review by Kong et al. on page 247–256.

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13.
《中国化学》2018,36(4):266-266
The inside cover picture shows a temperature controllable porphyrin aluminum catalyst using 5,10,15,20‐tetra(1,2,3,4,5,6,7,8‐octahydro‐1,4:5,8‐dimethanoanthracen‐9‐yl)porphyrin as ligand, which showed significantly temperature‐responsive selectivity in the coupling reaction of CO2 and PO. Only cycloaddition reaction happened at temperature above 75 °C to produce 100% CPC, whereas copolymerization became dominant to afford PPC with selectivity over 91% at temperature below 50 °C. More details are discussed in the article by Wang et al. on page 299–305.

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14.
《中国化学》2017,35(9):1478-1478
The back cover picture shows the asymmetric synthesis of α ‐substituted mercaptoglycine via nickel(II) complex. The α ‐substituted mercaptoglycine is an important framework of various peptide drugs and nickel(II) complex can be utilized to generate single enantiomer of α ‐substituted amino acid efficiently. This work establishes an efficient method to access α ‐substituted mercaptoglycine with good yield and high stereoselectivity, which can promote the design of new peptide drugs in a broad scope. More details are discussed in the article by Wang et al. on page 1383‐1390.

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15.
《中国化学》2018,36(5):472-472
The back cover picture shows a novel synthesis of 1,3‐oxazin‐6‐ones from enamides with CO2 through C—H carboxylation and one‐pot cyclization. The concept of “CO2 = CO + O”, using CO2 to replace toxic CO and stoichiometric oxidant, guilds the development of this chemistry as well as green and safe synthetic methods in the future. More details are discussed in the article by Yu et al. on page 430–436.

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16.
《中国化学》2017,35(12):1902-1902
The back cover picture shows X‐ray near edge absorption spectroscopy has been applied to cathode materials for lithium‐ion batteries to explore its structure‐activity relationship. The result shows that in the Li‐rich cathode Li1.15Ni0.47Sb0.38O2, as a model system, Ti ions replaced the Li ions and then made an antistructure defect. It would change our understanding to the doped method for the cathode layer materials and benefit for designing other more powerful cathodes. In the picture, the road has been represented by the curve shape of the XANES of the as‐studied sample. The atomic arrangement around the Ti ion of the sample has been put into the tank position of the car. NSRL, National Synchrotron Radiation Laboratory, is the name of our laboratory. More details are discussed in the article by Chu et al. on page 1853–1860.

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17.
《中国化学》2017,35(8):1336-1336
The back cover picture shows schematic of direct in situ liquid cell TEM observation of electron bean induced growth and self‐assembly of nanoclusters in water with the aid of a triblock copolymer. The growth and self‐assembly of the Pt nanoclusters with the aid of triblock copolymer F127 are directly observed, and a surfactant guided nanocluster formation mechanism is proposed. Dramatic differences are found on the cluster forming behavior and final morphologies between thick and thin liquid regions. The difference in precursor availability and charging effects are attributed to the different growth behavior in different thickness regions. More details are discussed in the article by Chen et al. on page 1278–1283.

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18.
《中国化学》2018,36(1):1-1
The cover picture shows a protocol of a palladium‐catalyzed arylation of vinylarenes with diaryliodonium salts with the assistance of visible light. A palladium‐vinylarene complex may be excited via the visible light irradiation, where the kinetic isotope effect (kH/kD) was around 1.1. However under darkness, the reaction proceeded very slowly, and the kinetic isotope was found as 3.6, indicating the C—H bond cleavage step is the rate‐determining step. This protocol avoided high reaction temperature and enabled us to access a series of ortho tetra‐substituted vinylarene atropisomers with high enantiospecificity. More details are discussed in the article by Gu et al. on page 11–14.

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19.
《中国化学会会志》2018,65(2):157-157
In this paper , a new type of organic‐inorganic hybrid hydrogel was prepared under the condition of low air press using SiO2 nanoparticles as initiator. The products shows a novel microstructure and characteristics that increased salt resistance and proper water absorbency. The xerogel showed absorbencies of 102.8 g/g for 0.9 wt% NaCl solution, respectively. More details will be discussed by Dr. Haiwang Wang and his co‐workers on page 157–293 in this issue.

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20.
《中国化学》2018,36(2):171-171
The inside back cover picture shows the construction of neutral supramolecular polymeric films containing well‐defined metallacycles as the main scaffolds through combination of coordination‐driven self‐assembly with post‐electropolymerization. A new 120° triphenylamine substituted dicarboxylate donor ligand and the complementary 120° triphenylamine functionalized di‐Pt(II) acceptor were employed to build neutral multi‐triphenylamine functionalized 2‐D metallacycles with the well‐defined shape and size via the formation of oxygen‐to‐platinum coordination bonds. Subsequent post‐electropolymerization of the obtained neutral multi‐triphenylamine containing metallacycles allowed for fabrication of a new type of neutral polymeric film with well‐controlled cavity sizes and thickness, which may have potential applications in neutral molecule detection, separation, and capture. More details are discussed in the article by Yang et al. on page 134–138.

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