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1.
《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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2.
《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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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(7):671-671
Inside Back Cover picture shows The carps trying hard to make a successful jump over the Dragon Gate will change into fish‐dragons, which is a legend handed down in China over generations. The back cover picture shows photochemical and electrochemical CO2 transformations with organic compounds through the utilization of solar energy or electric energy, producing a series of valuable products, including carboxylic acids and hetero‐cyclic compounds. The combined utilization of both clean energy and CO2 has attracted increasing attention in sustainable development of renewable energy and green chemistry. Recent advances are summarized by He et al. on page 644–659.

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5.
《中国化学》2018,36(9):782-782
The inside cover picture shows that four effective routes are applied to the anode material to help it keep fit, which is out of shape due to the intake of sodium ions. As a result, the sodium ion batteries (SIBs) with this anode exhibit high electrochemical performances, so that they tend to meet the demand for large‐scale energy storage devices. In this review, four strategies based on structural designs are summarized in order to accommodate volume changes of anode materials in SIBs, including nanoarchitecture configuration, buffer matrix protection, cavity volume reservation, and interlayer spacing regulation. More details are discussed in the review by Fu et al. on page 866–874.

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6.
《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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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》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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9.
《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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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》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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12.
《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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13.
《中国化学》2017,35(8):1198-1198
The inside cover picture shows the excellent catalytic performance of Karstedt's catalyst for the hydrosilylation of olefins terminated with various functional groups (amino, alkoxyl, carboxylic, hydroxyl, aldehyde, etc. ) with the trimethoxysilane and triethoxysilane reagents in terms of the yield and selectivity. More details are discussed in the article by Gao et al. on page 1227–1230.

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14.
《中国化学》2018,36(10):889-889
The cover picture shows an electricity powered dehydrogenative [3+2] annulation reaction of (hetero)arylamines with tethered di‐, tri, and tetra‐substituted alkenes for the preparation of indoline and azaindoline products. The electrochemical reactions proceed through H2 evolution and thus avoid the use of stoichiometric chemical oxidants. This method, which is applicable to the preparation of highly functionalized (aza)indoline scaffold, enables the total synthesis of (±)‐hinckdentine A in 12 steps. More details are discussed in the article by Xu et al. on page 909–915.

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15.
The inside cover picture shows a palladium‐catalyzed asymmetric dihydroxylation of 1,3‐dienes with catechols utilizing chiral pyridinebis(oxazoline) ligand. The reaction is proposed to proceed via a cascade Wacker‐type hydroxypalladation/asymmetric allylation process. This methodology provides a direct and straightforward synthesis to prepare chiral 2‐substituted 1,4‐benzodioxane motifs in moderate to good yield and enantioselectivity from readily available starting materials. More details are discussed in the article by Gong et al. on page 226–232.

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16.
《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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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.
The cover image by Jun Fu and co-workers displays how thermochromic smart windows dynamically regulate building thermal exchange in different climates. Typical thermochromic materials, including vanadium dioxide, hydrogels, perovskites, ionic liquids, and liquid crystals, transform from transparent to opaque when the temperature changes. Smart windows block outdoor solar thermal in the summer, which prevents indoor temperature rising. Indoor thermal radiation is also inhibited in winter to warm the indoors. Building temperatures and energy efficiency are optimized by thermochromic smart windows. DOI: 10.1002/pol.20230408

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19.
《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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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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