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.

     

Back Cover: Dual Stereocontrol for Enantioselective Hydrogenation of Dihydroisoquinolines Induced by Tuning the Amount of N‐Bromosuccinimide (Chin. J. Chem. 2/2018)

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.

     

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.

     

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.

     

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: Palladium‐Catalyzed Intermolecular Oxidative Coupling Reactions of (Z)‐Enamines with Isocyanides through Selective β‐C(sp2)‐H and/or C=C Bond Cleavage (Chin. J. Chem. 8/2018)

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.

     

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.

     

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.

     

Cover Picture: Engineering SpyCatcher Variants with Proteolytic Sites for Less‐Trace Ligation (Chin. J. Chem. 2/2019)

The cover picture shows an approach toward less‐trace SpyTag‐SpyCatcher ligation. A proteolytic recognition sequence has been engineered into the second loop of SpyCatcher to produce SpyCatcher^DDDDK variant. The reaction between SpyTag and SpyCatcher^DDDDK is highly efficient both in vivo and in vitro, producing a stable covalent complex. The complex can be further cleaved at the second loop by enterokinase, resulting in only a small scar after ligation. This protocol adds to the expanding toolbox of genetically‐encoded peptide‐protein chemistry for protein topology engineering. More details are discussed in the article by Zhang et al. on page 113–118.

     

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.

     

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.

     

Inside Back Cover: Photochemical and Electrochemical Carbon Dioxide Utilization with Organic Compounds (Chin. J. Chem. 7/2018)

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.

     

Cover Picture: Oxidative Rearrangement of Isatins with Arylamines Using H2O2 as Oxidant: A Facile Synthesis of Quinazoline‐2,4‐diones and Evaluation of Their Antibacterial Activity (Chin. J. Chem. 12/2017)

The cover picture shows a green and highly efficient synthetic method for the synthesis of quinazoline‐2,4‐diones from readily available isatins and arylamines. This method is interesting in keeping with the notion of green chemistry because of the use of hydrogen peroxide as the terminal oxidant. The rearrangement oxidation exhibited good functional group tolerability, metal‐free catalysts, obviating the need for oxidants and only environmentally benign H₂O was released. Moreover, an antibacterial activity study was performed to evaluate the antimicrobial activities. The results showed that some of the testing compounds inhibited the growth of the Staphylococcus aureus (32 μg/mL) and Staphylococcus epidermidis (64 μg/mL), which could potentially solve the problem of multidrug resistance. More details are discussed in the article by Shang et al. on page 1835–1843.

     

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.

     

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.

     

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: Building up 1‐D, 2‐D,and 3‐D Polyiodide Frameworks by Finely Tuning the Size of Aryls on Ar‐S‐TTF in the Charge‐Transfer (CT) Complexes of Ar‐S‐TTFs and Iodine (Chin. J. Chem. 9/2018)

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.

     

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.

     

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 Cover: A Three‐Dimensional MnII‐[MoIII(CN)7]4– Ferrimagnet Containing Formate as a Second Bridging Ligand (Chin. J. Chem. 1/2019)

The inside cover picture shows a three‐dimensional Mn^II‐[Mo^III(CN)₇]^4– ferrimagnet containing formate as a second bridging ligand synthesized from the self‐assembly of the [Mo(CN)₇]^4– anion and the Mn²⁺ ion in the presence of ammonium formate. Due to their interesting magnetic properties, [Mo(CN)₇]^4– based molecular magnetic complexes have attracted continuous interests. However because of the high sensitivity of the Mo^III center to both air and light, reports on these compounds are quite few. By introducing a second short bridge ligand into the [Mo(CN)₇]^4– based materials, the first mixed [Mo(CN)₇]^4–/HCOO^– bridged molecule magnet with a critical temperature of 70 K can be constructed. More details are discussed in the article by Wang et al. on page 19–24.