Cover Picture: Understanding Zeolites Catalyzed Methanol‐to‐Olefins Conversion from Theoretical Calculations (Chin. J. Chem. 5/2018)

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.

     

Back Cover: Lactonization of C(sp2)—H Bonds in Enamides with CO2 (Chin. J. Chem. 5/2018)

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.

     

Cover Picture: Synthesis of Subnanometer‐Sized Gold Clusters by a Simple Milling‐Mediated Solid Reduction Method (Chin. J. Chem. 4/2018)

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.

     

Inside Cover: Upgrading CO2 by Incorporation into Urethanes through Silver‐Catalyzed One‐Pot Stepwise Amidation Reaction (Chin. J. Chem. 2/2018)

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.

     

Inside Cover: Effect of Brønsted/Lewis Acid Ratio on Conversion of Sugars to 5‐Hydroxymethylfurfural over Mesoporous Nb and Nb‐W Oxides (Chin. J. Chem. 10/2017)

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.

     

Cover Picture: Visible Light Accelerated Vinyl C–H Arylation in Pd‐Catalysis: Application in the Synthesis of ortho Tetra‐substituted Vinylarene Atropisomers (Chin. J. Chem. 1/2018)

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 (k_H/k_D) 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.

     

Cover Picture: Electrochemical Synthesis of (Aza)indolines via Dehydrogenative [3+2] Annulation: Application to Total Synthesis of (±)‐Hinckdentine A (Chin. J. Chem. 10/2018)

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.

     

Cover Picture: A Three‐dimensional Non‐fullerene Small Molecule Acceptor for Solution‐processed Organic Solar Cells (Chin. J. Chem. 11/2017)

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.

     

Cover Picture: Nickel‐Catalyzed Cross‐Electrophile Coupling of Aryl Bromides with Pyrimidin‐2‐yl Tosylates (Chin. J. Chem. 9/2017)

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.

     

Inside Cover: Synthetic Strategies for Constructing Two‐Dimensional Metal‐Organic Layers (MOLs): A Tutorial Review (Chin. J. Chem. 8/2018)

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.

     

Back Cover: Asymmetric Synthesis of Chiral α‐Substituted Mercaptoglycine Derivatives via α‐Sulfenylation of Ni(II) Complex of Glycine and S‐Substituted 4‐Methylbenzenesulfonothioate (Chin. J. Chem. 9/2017)

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.

     

Inside Cover: General Reductive Amination of Aldehydes and Ketones with Amines and Nitroaromatics under H2 by Recyclable Iridium Catalysts (Chin. J. Chem. 9/2017)

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.

     

Inside Back Cover: Fabrication of Neutral Supramolecular Polymeric Films via Post‐electropolymerization of Discrete Metallacycles (Chin. J. Chem. 2/2018)

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.

     

Back Cover: Internally Reuse Waste: Catalytic Asymmetric One‐Pot Strecker Reaction of Fluoroalkyl Ketones,Anilines and TMSCN by Sequential Catalysis (Chin. J. Chem. 4/2018)

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.

     

Cover Picture: Rapid Detection of Sildenafil Drugs in Liquid Nutraceuticals Based on Surface‐Enhanced Raman Spectroscopy Technology (Chin. J. Chem. 10/2017)

The cover picture shows a rapid detection of sildenafil drugs in liquid nutraceuticals based on surface‐enhanced Raman spectroscopy technology. A detailed attribution analysis by density functional theory (DFT) was used to guide specific experiments. The Raman signals were obtained from a silver colloid (Ag col) substrate, and they increased in the presence of the mineral salt, potassium iodide (KI). These methods detected sildenafil in aqueous solutions as low as 1 µg/mL with high signal uniformity (RSD = 3.77%). Raman technology detected low contents of sildenafil drugs in liquid nutraceuticals, not in solid samples. Therefore, SERS technology has great potential for on‐site and real‐time detection of illegal drugs in water and in liquid nutraceuticals. More details are discussed in the article by Hasi et al. on page 1522–1528.

     

Inside Cover: Ir‐Catalyzed Asymmetric Hydrogenation of α‐Alkylidene β‐Lactams and Cyclobutanones (Chin. J. Chem. 7/2018)

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.

     

Cover Picture: Nitrogen Analogues of o‐Quinodimethane with Unexpected non‐Kekulé Diradical Character (Chin. J. Chem. 6/2018)

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.

     

Inside Cover: Temperature‐responsive Catalyst for the Coupling Reaction of Carbon Dioxide and Propylene Oxide (Chin. J. Chem. 4/2018)

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.

     

Back Cover: Synthesis,Nematicidal Activity,and 3D‐QSAR of Novel 1,3,4‐Oxadiazole/ Thiadiazole Thioether Derivatives (Chin. J. Chem. 10/2018)

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.

     

Back Cover: Synthesis,Structure and Biological Activities of Novel 2‐(Trifluoromethyl)‐ 6‐arylimidazo[2,1‐b][1,3,4]‐thiadiazole (bis‐)Mannich Base Derivatives Containing Substitutedpiperazine Moiety (Chin. J. Chem. 7/2018)

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.