Angewandte Chemie International Edition

Li, Jian; Han, Xu; Wang, Dongmei; Zhu, Lei; Ha‐Thi, Minh‐Huong; Pino, Thomas; Arbiol, Jordi; Wu, Li‐Zhu; Nawfal Ghazzal, Mohamed

doi: 10.1002/anie.202210242pmid: 35985984

With a direct band gap, superior charge carrier mobility, and uniformly distributed pores, graphdiyne (GDY) has stimulated tremendous interest from the scientific community. However, its broad application is greatly limited by the complicated multistep synthesis process including complex deprotection of hexakis‐[(trimethylsilyl)ethynyl]benzene (HEB‐TMS) and peeling of GDY from the substrates. Here, we describe a deprotection‐free strategy to prepare GDY powder by directly using HEB‐TMS as the monomer. When CuCl was used as the catalysts in DMF solvent, the yield of GDY powder reached ≈100 %. More interestingly, uniformly dispersed CuO nanoparticles with an average diameter of ≈2.9 nm were in situ formed on GDY after the reaction. The prepared CuO/GDY was demonstrated an excellent co‐catalyst for photocatalytic hydrogen evolution, comparable to the state‐of‐art Pt co‐catalyst. The deprotection‐free approach will widen the use of GDY and facilitate its scaling up to industrial level.

Huo, Qingqing; Gao, Yue; Wu, Wenbo; Hu, Shuai; Zhang, Zifan; Li, Zhi; Tian, Yuling; Quan, Peng; Li, Wen; Liu, Dongfei

doi: 10.1002/anie.202208738pmid: 35925712

The control of cargo phase‐transfer is of interest for many applications in science and technology. Herein, we report a simple, versatile and robust method to block the phase‐transfer of cargo colloids by interfacial self‐assembled amphiphilic polymer molecules. After simply increasing the concentration of amphiphilic polymers, the orientation of interfacial polymer molecules changed from flat to upright, forming a thick three‐dimensional polymer layer at the oil‐water interface. Even under fierce external force, this thick interfacial layer robustly prevented the phase‐transfer of cargo colloids, resulting in an ultrahigh encapsulation efficiency (up to 97.1 %) for proteins and peptides. One single injection of high insulin‐loaded microcomposites (58.3 wt%) kept the blood glucose level within the normoglycemic state for 10 days in type 1 diabetic rats. The mass of administrated amphiphilic polymers was 1889 times smaller than that of microcomposites prepared with non‐amphiphilic ones.

Bera, Abhijit; Henkel, Stefan; Mieres‐Perez, Joel; Andargie Tsegaw, Yetsedaw; Sanchez‐Garcia, Elsa; Sander, Wolfram; Morgenstern, Karina

doi: 10.1002/anie.202212245pmid: 36056533

Chirality switching of self‐assembled molecular structures is of potential interest for designing functional materials but is restricted by the strong interaction between the embedded molecules. Here, we report on an unusual approach based on reversible chirality changes of self‐assembled oligomers using variable‐temperature scanning tunneling microscopy supported by quantum mechanical calculations. Six functionalized diazomethanes each self‐assemble into chiral wheel‐shaped oligomers on Ag(111). At 130 K, a temperature far lower than expected, the oligomers change their chirality even though the molecules reside in an embedded self‐assembled structure. Each chirality change is accompanied by a slight center‐of‐mass shift. We show how the identical activation energies of the two processes result from the interplay of the chirality change with surface diffusion, findings that open the possibility of implementing various functional materials from self‐assembled supramolecular structures.

Jia, Yi; Yan, Xuehai; Li, Junbai

doi: 10.1002/anie.202207752pmid: 35856468

Dynamic covalent chemistry (DCC) is fascinating because of its dual nature. It perfectly combines the reversible nature of noncovalent bonds with the robustness of covalent bonds, effectively enhancing the stability of assemblies and meanwhile giving rise to unprecedented properties. Therefore, integration of DCC with supramolecular chemistry has emerged as a versatile and an extraordinarily useful approach in directing peptide assembly. This Minireview focuses on a recent strategy, which exploits dynamic Schiff base chemistry in combination with supramolecular chemistry, to mediate dipeptide assembly toward nanoarchitectonics. Diversified structures, new emergent properties, and their related applications are highlighted. Lastly, the opportunities and prospects in this exciting field are also introduced.

Zheng, Rui; Fu, Zhi‐Hua; Deng, Wei‐Hua; Wen, Yingyi; Wu, Ai‐Qian; Ye, Xiao‐Liang; Xu, Gang

doi: 10.1002/anie.202212797pmid: 36068192

The layer‐by‐layer liquid‐phase epitaxy (LBL‐LPE) method is widely used in preparing metal–organic framework (MOF) thin films with the merits of controlling thickness and out‐of‐plane orientation for superior performances in applications. The LBL‐LPE growth mechanism related to the grain boundary, structure defect, and orientation is critical but very challenging to study. In this work, a novel “in‐plane self‐limiting and self‐repairing” thin‐film growth mechanism is demonstrated by the combination study of the grain boundary, structure defect, and orientation of Cu3(HHTP)2‐xC thin film via microscopic analysis techniques and electrical measurements. This mechanism results a desired high‐quality MOF thin film with preferred in‐plane orientations at its bottom for the first time and is very helpful for optimizing the LBL‐LPE method, understanding the growth cycle‐dependent properties of MOF thin film, and inspiring the investigations of the biomimetic self‐repairing materials.

Yang, Yuhao; Hammond, Gerald B.; Umemoto, Teruo

doi: 10.1002/anie.202211688pmid: 36066942

Fluorination of carbanions is pivotal for the synthesis of fluorinated compounds, but the current N‐F fluorinating agents have significant drawbacks due to many reactive locations that surround the reactive N−F site. By developing a sterically hindered N‐fluorosulfonamide reagent, namely N‐fluoro‐N‐(tert‐butyl)‐tert‐butanesulfonamide (NFBB), we discovered a conceptually novel base‐catalyzed, self‐sustaining fluorination of active methylene compounds and achieved the high‐yielding fluorination of the hitherto difficult highly basic (hetero)aryl and alkenyl lithium species. In the former, the mild and high yield fluorination of active methylene compounds exhibited wide functional group tolerance and its novel catalytic fluorination‐deprotonation cycle mechanism was demonstrated by deuterium‐tracing experiments. In the latter, NFBB reacted with a variety of highly basic (hetero)aryl and alkenyl lithium species to provide the desired fluoro (hetero)arenes and alkenes in unprecedented high or quantitative yields.

Zhang, Wen‐Jian; Chang, Zi‐Xuan; Bai, Wei; Hong, Chun‐Yan

doi: 10.1002/anie.202211792pmid: 36082798

Worm‐like micelles have attracted great interest due to their anisotropic structures. However, the experimental conditions for obtaining worm‐like micelles are very restricted, which usually causes seriously poor reproducibility. In this work, significantly enhanced accessibility of worm‐like micelles is realized by in situ crosslinking polymerization‐induced self‐assembly (PISA). The reproducibility of worm‐like micelles is greatly improved due to the significantly enlarged experimental windows of worm‐like micelles in the morphology diagram. Moreover, the reliability of the methodology to enhance the accessibility of worm‐like micelles has been demonstrated in various in situ crosslinking PISA systems. The greatly enhanced accessibility and reproducibility of worm‐like micelles is undoubtedly cost‐effective especially in scale‐up production, which paves the way for further application of worm‐like micelles with various compositions and functionalities.

Yamada, Michio; Kurihara, Yukiyo; Koizumi, Masaaki; Tsuji, Kasumi; Maeda, Yutaka; Suzuki, Mitsuaki

doi: 10.1002/anie.202212279pmid: 36068173

Face‐to‐face noncovalent arene−fullerene interactions are important in several research fields such as synthetic chemistry, materials chemistry, and medicinal chemistry; however, their nature and strength are still poorly understood. In this study, we prepare a fullerene‐based torsion balance containing thioanisole, phenol, naphthalene, azulene, and pyrene moieties as a unimolecular model system. Moreover, we compare the folding free energies between the folded and the unfolded conformers of a series of the molecular torsion balances to quantify noncovalent interactions between arenes and the fullerene surface. This work demonstrates that the contributions of polarizabilities, anionic charges, electronic dipole moments, and the number of arene rings to the interactions can be experimentally measured by analyzing the folding equilibrium of the molecular torsion balances.

Scharnhölz, Moritz Theodor; Coburger, Peter; Gravogl, Lisa; Klose, Daniel; Gamboa‐Carballo, Juan José; Le Corre, Grégoire; Bösken, Jonas; Schweinzer, Clara; Thöny, Debora; Li, Zhongshu; Meyer, Karsten; Grützmacher, Hansjörg

doi: 10.1002/anie.202205371pmid: 35661524

Reaction of the 6π‐electron aromatic four‐membered heterocycle (IPr)2C2P2 (1) (IPr=1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐dihydro‐2H‐imidazol‐2‐ylidene) with [Fe2CO9] gives the neutral iron tricarbonyl complex [Fe(CO)3‐η3‐{(IPr)2C2P2}] (2). Oxidation with two equivalents of the ferrocenium salt, [Fe(Cp)2](BArF24), affords the dicationic tricarbonyl complex [Fe(CO)3‐η4‐{(IPr)2C2P2}](BArF24)2 (4). The one‐electron oxidation proceeds under concomitant loss of one CO ligand to give the paramagnetic dicarbonyl radical cation complex [Fe(CO)2‐η4‐{(IPr)2C2P2}](BArF24) (5). Reduction of 5 allows the preparation of the neutral dicarbonyl complex [Fe(CO)2‐η4‐{(IPr)2C2P2}] (6). An analysis by various spectroscopic techniques (57Fe Mössbauer, EPR) combined with DFT calculations gives insight into differences of the electronic structure within the members of this unique series of iron carbonyl complexes, which can be either described as electron precise or Wade–Mingos clusters.

Ganesan, Elavenil; Custer, Thomas; Lawzer, Arun‐Libertsen; Guillemin, Jean‐Claude; Kołos, Robert

doi: 10.1002/anie.202210521pmid: 36052447

We report the first detection of phosphorescence from the phosphaethynyl radical. This rare instance of quartet‐doublet emission, studied here in solid argon, is presumably promoted by efficient intersystem crossing from the originally photoexcited doublet (B2Σ+) to the adjacent second quartet state, 14Δ. Vibronic progressions were traced for the a4Σ+‐X2Σ+ and a4Σ+‐A2Пi systems from their origins up to (v′=0)→(v′′=5) and (v′=0)→(v′′=2) bands, respectively. The measured phosphorescence lifetime is 108 ± 3 ms.