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.
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.
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.
The cover picture shows a highly enantioselective organocatalytic protonation of monofluorinated silyl enol ethers to α‐secondary α‐fluoroketones using water as proton source. Notably, in the presence of D2O and MeOD, the facile access of chiral α‐deuterated α‐fluoroketones in excellent enantioselectivity is achieved. More details are discussed by Zhou et al. on page 799–806.
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.
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.
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.
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.
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.
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.
The back cover picture shows the first LA‐catalyzed [3+2]IMCC of GDA‐epoxides with carbon‐carbon double bonds. This provides an efficient and general strategy for construction of bridged oxa‐[n.2.1] skeletons. A novel SN‐like mechanism through a carbon‐carbon bond cleavage of epoxide ring has been proposed. The colorful fireworks in the picture imply the generation of skeletal diversity from the epoxide‐diene, and express a dedication to the 100th Anniversary of Nankai University as well. More details are discussed in the article by Wang et al. on page 695–699.
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.
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.
The inside back cover picture shows a simple and efficient Cu(II )‐catalyzed ligand‐free oxidation of diarylmethanes and secondary alcohols using 70% TBHP in water. A series of diarylmethanes were directly oxidized into diaryl ketones in 67%–98% yields. Additionally, various secondary alcohols were also transformed into the desired products in 48%–98% yields. Importantly, the catalytic system in the absence of any organic solvent, surfactant, or phase transfer agent, had a wide substrate scope and a high tolerance for various functional groups. More details are discussed in the article by Liu et al. on page 1391–1395.
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.
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.
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.
The inside back cover picture shows the controllable skeleton rearrangement of 3‐substituted cyclobutanones under basic conditions. In this paper, a series of 3‐substituted cyclobutanones with different Z group underwent skeleton rearrangement with the treatment of K3PO4 and 18‐crown‐6 ether. Various lactones, lactams and acids were afforded in this concise reaction. More interestingly, an eight‐membered ring was produced with pentaflurophenyl group as a good leaving group. More details are discussed in the article by Lu et al. on page 1103—1106.
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.
