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 cover picture shows facile photochemical synthesis, direct in situ TEM characterization, and effective catalytical applications of sponge‐like porous Pd nano particles. In situ liquid cell TEM observation not only confirms the actual existence of the sponge‐like Pd in a liquid solution, but also shows such Pd nanostructure is in a dynamic stable state, which is beneficial for the material exchange and the catalytic performance improvement. The expected catalytic activity improvement is supported by such as the 4‐nitrophenol reduction reactions, which is important both for the environment and the industry. More details are discussed in the article by Chen et al. on page 565–569.
The inside cover picture shows the hydrogen transfer process of the production of acetic acid from ethanol and water mixture catalyzed by iridium catalyst owning bpyO ligand. A DFT mechanistic study indicates that the cooperation of the iridium center and bpyO ligand plays an important role in the catalytic activity, and that the hydrogen release process from the iridium center is the rate‐determining step. More details are discussed in the article by Lei et al. on page 883–886.
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.
The cover picture shows that sequential 1,1‐dihydrosilylation of terminal aliphatic alkynes with primary silanes enabled by one earth‐abundant cobalt catalyst has been developed. This protocol is operationally simple using readily available aliphatic alkynes, including simple acetylene and complex drug derivative, for efficient access to valuable gem‐bis(dihydrosilyl)alkanes in highly regioselective and atom‐economic manners. Corresponding asymmetric transformations are achieved with excellent enantioselectivities. More details are discussed in the article by Lu et al. on page 457–461.
The cover picture shows Schilancidilactones A, B and Schilancitrilactones A, B, C all belong to schinortriterpenoid. Preliminary bioassay shows some of them possess fascinating bioactivities, such as antitumor, antihepatitis, and anti‐HIV‐1 activities. The total synthesis of Schilancidilactones A, B and Schilancitrilactones A, B, C has been accomplished from the common intermediates for the first time by Tang group. An intramolecular radical cyclization, late‐stage halogenation and AIBN‐mediated or Ni‐catalyzed intermolecular radical cross coupling reaction were employed as the key steps. More details are discussed in the article by Tang et al. on page 255–268.
The inside cover picture shows the development of chiral pyridoxal and pyridoxamine catalysts by mimicking vitamin B6‐dependent enzymes. These chiral pyridoxals and pyridoxamines displayed extraordinary catalytic performances in asymmetric biomimetic transamination and Mannich reaction, to give various chiral α‐amino acids and α,β‐diamino acid esters in good yields with excellent diastero‐ and/or enantioselectivities. The research has provided some useful information for further applications of the catalytic power of vitamin B6 in the area of asymmetric cayalysis. More details are discussed in the article by Zhao et al. on page 103–112.
The cover picture shows a synergistically directed assembly route towards novel multi‐component coordination architectures driven by aromatic donor‐acceptor and coordination interactions. The huge structural discrepancies between coronene donor present and absent experiments clearly prove the significance of aromatic donor‐accepter pairs and their inherent cooperation mechanism in these assembly processes. More details are discussed by Bu et al. on page 871–877.
The cover picture shows A new strategy for preparing antimicrobial peptides from the natural occurring peptide gramicidin A has been developed by simply removing its N‐terminal formyl group and decoration at the terminal NH2 group. The peptides are able to selectively insert into Gram‐positive bacterial membrane to form transmembrane channels but not that of erythrocyte membrane, which leads to their high antimicrobial activity and low hemolytic toxicity. More details are discussed in the article by Hou et al. on page 25–29.
The cover picture shows a new silver cluster‐assembled material of {[Ag18(StBu)10(CF3COO)2(PhPO3)(PhPO3H)4(bpy‐NH2)2]?(PhPO3H2)}n, being prepared by a facile one‐pot method. Ag18bpy‐NH2 exhibits reversible luminescent mechanochromism between blue and cyan upon external mechanical stimulation and treatment with ethanol‐acetone. In addition, the as‐synthesized Ag18bpy‐NH2 also showed reversible luminescent thermochromism from blue at room temperature to bluish white at 83 K and vice versa. More details are discussed in the article by Zang et al. on page 1120–1124.
In this paper, we design a new interrupted AST‐type zeolitic imidazolate framework with cub and interrupted ast cages, which exhibits permanent porosity, high hydrophobicity and strong solid‐state photoluminescent properties. More details are discussed in the article by Wang & Zhang et al. on page 449–452.
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 SpyCatcherDDDDK variant. The reaction between SpyTag and SpyCatcherDDDDK 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.
The cover picture shows a simple, inexpensive and robust method on defluorosilylation of diverse fluoroalkenes with silylboronates in the presence of alkoxy base to directly synthesize various silylated fluoroalkenes. Density functional theory calculations revealed that transient silyl anion complex undergoes SN2’ or SNV substitution, which is responsible for this base‐mediated defluorosilylation reaction, thus obviating the need for copper salts. More details are discussed in the article by Shi et al. on page 1009–1014.
The inside cover picture shows an electrochemical oxidative Csp3‐H/S‐H activation with hydrogen evolution for the synthesis of tetrasubstituted olefins. This method features very high atom economy, besides hydrogen gas, under the base‐free, transition met‐al‐free, and oxidants‐free conditions, no other by‐products were generated. More details are discussed in the article by Lei et al. on page 547–551.
Glycerol molecules can be selectively converted into 1,2‐propanediol in water by the way of Ni‐based Great‐Wall Catalysts with Beacon‐like macropores and Passage‐like mesoporous channels. Otherwise, an amount of by‐product lactic acid was produced via rearrangement from glycerol. More details are discussed in the article by Zhang & Ma et al. on page 439–444.
The function of the type II peptidyl carrier protein (PCP) ColA1a in collismycin (COL) biosynthesis was characterized in this study. ColA1a was involved in the selection and loading of picolinic acid (PA), instead of normal amino acid substrates, as the origin of ring B in COLs. The 2.1 Å crystal structure of ColA1a was solved. Primary and tertiary structural comparison of ColA1a with other PCPs revealed the structural basis for their typical α‐helical bundles. More details are discussed in the article by Ma et al. on page 963—969.
The back cover picture shows a supramolecularly‐controlled topochemical reaction of conjugated dienes under irradiation in homogeneous system. Using this method, the cyclooctadiene‐cored derivatives are synthesized very efficiently. Moreover, the cyclooctadiene tetraimidazolium derivatives can be applied as fluorescent chemosensors for thymine in aqueous solution at physiological pH (7.4). More details are discussed in the article by Han et al. on page 1040—1044.
The cover picture shows the copper‐catalyzed Ullmann‐Ma reaction of aryl halides with nucleophiles by the assistance of two‐generation ligands, amino acids and oxalic diamides or related amides. Ullmann‐Ma reaction is one of the most important transformations for the construction of aryl carbon‐carbon and carbon‐heteroatom bonds in organic chemistry. For the details about the history, development, scope and applications of Ullmann‐Ma reaction, please see the article by Cai et al. on page 879–893.
A copper‐catalyzed aerobic oxidative ring expansion reaction of isatins with 1,2,3,4‐tetrahydroisoquinoline for the synthesis of tetracyclic quinazolinones has been developed. The capacity of the resultant 5H‐isoquinolino[1,2‐b]quinazolin‐8(6H)‐one for a range of palladium‐catalyzed directing C—H activation has been further demonstrated, thus giving a broader access to diverse tetracyclic quinazolinones. More details are discussed in the article by Xiao and Deng et al. on page 87—92.
Cryo‐electron diffraction tomography (Cryo‐EDT) has been developed to determine the crystal structures of covalent organic frameworks (COFs) and their host‐guest interaction at the atomic precision, whose crystals are only submicron‐sized, organic, porous, and dynamic. The keys of 3D electron diffraction (3D‐ED) techniques are low‐dose beam, sample cryo‐handling, fast data collection, sensitive detector, and direct space structure solution. We envision the development of COF chemistry will be propelled by such powerful 3D‐ED techniques for a better understanding at the molecular level and correlation of structures to chemicophysical properties. More details are discussed in the article by Zhang et al. on page 1153—1166.
