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1.
《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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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》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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4.
《中国化学》2017,35(10):1480-1480
The inside cover picture shows the excellent catalytic performance of mesoporous Nb and Nb‐W oxides catalysts for the conversion of glucose to 5‐hydroxymethylfurfural. The catalytic activity and selectivity for all Nb‐W oxides vary according to the ratio of Brønsted to Lewis acid sites. The highest HMF selectivity of 52% was achieved over Nb7W3 oxide catalyst. More details are discussed in the article by He et al. on page 1529–1539.

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5.
《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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6.
《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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7.
《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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8.
《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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9.
《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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10.
《中国化学》2018,36(9):781-781
The cover picture shows The arylthio‐substituted tetrathiafulvalenes (Ar‐S‐TTFs) are electron donors having three reversible states, neutral, cation radical, and dication. The charge‐transfer (CT) between Ar‐S‐TTFs and iodine (I2) occurs in solution, whereas the Ar‐S‐TTFs are partially at cation radical state. In CT complexes of Ar‐S‐TTFs with I2, the charged states of Ar‐S‐TTFs are distinctly increased, say, the dicationic state is observed. The iodine components in CT complexes show various structures including 1‐D polymeric chain, and 2‐D and 3‐D iodine networks. More details are discussed in the article by Shao et al. on page 845–850.

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11.
The cover picture shows Schilancidilactones A, B and Schilancitrilactones A, B, C all belong to schinortriterpenoid. Preliminary bioassay shows some of them possess fascinating bioactivities, such as antitumor, antihepatitis, and anti‐HIV‐1 activities. The total synthesis of Schilancidilactones A, B and Schilancitrilactones A, B, C has been accomplished from the common intermediates for the first time by Tang group. An intramolecular radical cyclization, late‐stage halogenation and AIBN‐mediated or Ni‐catalyzed intermolecular radical cross coupling reaction were employed as the key steps. More details are discussed in the article by Tang et al. on page 255–268.

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12.
《中国化学》2018,36(7):672-672
The back cover picture shows a convenient and practicable synthesis of novel 2‐(trifluoromethyl)‐6‐arylimidazo[2,1‐b][1,3,4]‐thiadiazole (bis‐)Mannich base derivatives containing various substitutedpiperazine motif. Based on the C‐Mannich reaction of unusual intermediate – 2‐(trifluoromethyl)‐6‐arylimidazothiadiazole, with (4‐substituted) piperazine and formaldehyde in ethanol and acetic acid, the target compounds have been achieved conveniently with satisfying yields. Meanwhile, the cover picture shows that some of the target compounds possess favourable pesticidal activities (e.g. fungicidal and insecticidal). This research will provide important information for relevant synthetic studies of imidazole‐fused‐heterocycle derivatives and their applications in agrochemical area. More details are discussed in the article by Wang et al. on page 635–638.

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13.
《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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14.
《中国化学》2018,36(7):566-566
The inside cover picture shows Chiral β‐lactams and cyclobutanones are present in numerous natural and pharmaceutical products. A direct preparation of chiral four‐membered rings via metal‐catalyzed asymmetric hydrogenation has not been described yet. In this article, we report an Ir/BiphPHOX‐catalyzed asymmetric hydrogenation of α‐alkylidene β‐lactams and cyclobutanones for the direct preparation of β‐lactams and cyclobutanones bearing an α‐substituted stereocenter. Our tropos phosphine‐oxazoline biphenyl ligand is essential for the preparation of the desired products with high enantioselectivities. More details are discussed in the article by Zhang et al. on page 612–618.

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15.
《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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16.
《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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17.
《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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18.
《中国化学》2017,35(10):1650-1650
The back cover picture shows a photocatalytic remediation of polycyclic aromatic hydrocarbons (PAHs) from wastewater with graphene oxide (GO) enwrapped silver phosphate as visible light‐driven photocatalysts. PAHs are a class of highly mutagenic and carcinogenic organic pollutants that pose serious threats to human health and the ecosystem. GO/Ag3PO4 was synthesized by a simple precipitation method. The photocatalysts exhibited superior photocatalytic activity and stability. The degradation efficiency of naphthalene, phenanthrene and pyrene could reach 49.7%, 100.0% and 77.9%, respectively within 5 min irradiation. Meanwhile, the efficiencies of 44.6%, 95.2% and 83.8% were achieved for naphthalene, phenanthrene and pyrene degradation even after 5 times of recycling in the GO/Ag3PO4‐PAHs photocatalysis system. More details are discussed in the article by Bao et al. on page 1549–1558.

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19.
《中国化学》2017,35(7):1025-1025
The cover picture shows shows the construction of crown etherstoppering [3]rotaxanes based on N ‐hetero crown ether host. Usually, crown ethers play the role of host macrocycles to combine with the guest molecules in the construction of rotaxanes. Based on the fact that crown ethers have large dimension, two [3]rotaxanes containing four crown ether units were designed and synthesized, of which, two N ‐hetero crown ether components were employed as the macrocyclic hosts to assemble the mechanically interlocked framework by using a template‐directed clipping reaction while bis (metaphenylene‐26‐crown‐8) located on two sides of template diammonium acting as the stoppering groups of [3]rotaxanes. More details are discussed in the article by Yin et al. on page 1050–1056.

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20.
《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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