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1.
《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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2.
《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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3.
《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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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(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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6.
《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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7.
《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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8.
《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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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.
《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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12.
《中国化学》2018,36(6):473-473
The cover picture shows para‐Quinodimethane (p‐QDM) and ortho‐quinodimethane (o‐QDM) are two typical examples of Kekulé‐type delocalized diradicals. The cover picture shows that the replacement of the carbinyl centers with isoelectronic aminium centers leads to the formation of isolable nitrogen analogues of o‐QDM. In contrast to o‐QDM, the nitrogen analogues exhibit unexpected non‐Kekulé diradical characters and features open‐shell singlet ground states with thermally accessible triplet states. More details are discussed in the article by wang et al. on page 487–490.

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13.
《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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14.
《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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15.
《中国化学》2017,35(11):1651-1651
The cover picture shows a new three‐dimensional non‐fullerene small molecular acceptor for solution‐processed organic solar cells. The acceptor was named SFTTIC using spiro‐bifluorene as the core unit linking with four thieno[3,2‐b ]thiophenes and end‐capped with 2‐(3‐oxo‐2,3‐dihydro‐1H ‐inden‐1‐ylidene)malononitrile. SFTTIC has a high absorption coefficient, good thermal stability and appropriate energy levels and the optimized power conversion efficiency (PCE) of 5.66% was achieved for the devices with PBDB‐T as donor material. These results indicate that the 3D non‐fullerene small molecule is potential for achieving high photovoltaic performance. More details are discussed in the article by Chen et al. on page 1687–1692.

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16.
《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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17.
18.
《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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19.
《中国化学》2018,36(4):372-372
A highly enantioselective one‐pot Strecker reaction of α‐fluoroalkyl α‐aryl ketones, anilines, and TMSCN is disclosed, which simultane‐ously reuses water byproduct and catalyst from the ketimine formation step as a promoter and an additive to improve the reactivity and enantioselectivity of the subsequent Strecker reaction, respectively. The picture shows that the chiral bifunctional tertiary amine mediated asymmetric Strecker reaction is irrigated by the water generated in the p‐TsOH catalyzed ketimine formation, and fertilized by the remaining acid catalyst. More details are discussed in the article by Zhou et al. on page 321–328.

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20.
《中国化学》2018,36(9):888-888
The back cover picture shows Genkwadane A was isolated from the flower buds of Daphne genkwa which shows bioactivity against HeLa, HepG2, HT‐1080, MCF‐7, A549, U‐937, K562 and HL60 cell lines. It is the first time that a daphnane diterpenoid bearing a 1,10‐double bond was isolated. In this paper, B. Liu and co‐workers report asymmetric synthesis of the ring A substructure of genkwadane A in 10 steps from D‐tartrate derivative. More details are discussed in the article by Liu et al. on page 831–836.

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