Angewandte Chemie International Edition

doi: 10.1002/anie.202207867pmid: 35701179

Chen, Jian; Zhang, Shuai; Pan, Xin; Li, Ruiqian; Ye, Shi; Cheetham, Anthony K.; Mao, Lingling

doi: 10.1002/anie.202205906pmid: 35535865

Chiral hybrid metal halides with a high dissymmetry factor (glum) and a superior photoluminescence quantum yield (PLQY) are promising candidates for circularly polarized luminescence (CPL) light sources. Here, we report eight new chiral hybrid manganese halides, crystallizing in the non‐centrosymmetric space group P212121 and showing intense CPL emissions. Oppositely‐signed circular dichroism (CD) and CPL signals are detected according to the R‐ and S‐configurations of the chiral alkanolammonium cations. Time‐resolved PL spectra show long averaged decay lifetimes up to 1 ms for (R‐3‐quinuclidinol)MnBr3 (R‐1). The glum of polycrystalline samples for coordinated structures (23×10−3) is more than doubled compared with the non‐coordinated ones (8.5×10−3), due to the structural variations. R‐1 exhibit both a high glum and a high PLQY (50.2 %). The effective chirality transfer mechanism through coordination bonds, with strongly emissive MnII centers, enables a new class of high‐performance CPL materials.

Wang, Lei; Lu, Wenxin; Zhang, Jiwu; Chong, Qinglei; Meng, Fanke

doi: 10.1002/anie.202205624pmid: 35606326

One of the most straightforward approaches to access chiral silanes is catalytic enantioselective hydrosilylation. Although significant advances have been achieved in enantioselective construction of either a carbon‐stereogenic center or a silicon‐stereogenic center through enantioselective hydrosilylation, simultaneous establishment of a carbon‐ and a silicon‐stereogenic center in an acyclic molecule through a single intermolecular hydrosilylation remained undeveloped. Herein, an unprecedented cobalt‐catalyzed regio‐, diastereo‐ and enantioselective hydrosilylation of 1,3‐dienes is presented, enabling construction of a carbon‐ and a silicon‐stereogenic center in a single intermolecular transformation. A wide range of chiral silanes bearing a carbon‐ and a silicon‐stereogenic center were generated in high efficiency and stereoselectivity. Functionalization of the enantioenriched silanes delivered a variety of valuable chiral building blocks that are otherwise difficult to access.

Saito, Yusuke; Honda, Ryutaro; Akashi, Sotaro; Takimoto, Hinata; Nagao, Masanori; Miura, Yoshiko; Hoshino, Yu

doi: 10.1002/anie.202206456pmid: 35567515

Synthetic polymer nanoparticles (NPs) that recognize and neutralize target biomacromolecules are of considerable interest as “plastic antibodies”, synthetic mimics of antibodies. However, monomer sequences in the synthetic NPs are heterogeneous. The heterogeneity limits the target specificity and safety of the NPs. Herein, we report the synthesis of NPs with uniform monomer sequences for recognition and neutralization of target peptides. A multifunctional oligomer with a precise monomer sequence that recognizes the target peptide was prepared via cycles of reversible addition–fragmentation chain transfer (RAFT) polymerization and flash chromatography. The oligomer or blend of oligomers was used as a chain transfer agent and introduced into poly(N‐isopropyl acrylamide) hydrogel NPs by radical polymerization. Evaluation of the interaction with the peptides revealed that multiple oligomers in NPs cooperatively recognized the sequence of the target peptide and neutralized its toxicity. Effect of sequence, combination, density and molecular weight distribution of precision oligomers on the affinity to the peptides was also investigated.

Sabat, Nazarii; Zhou, Weiping; Gandon, Vincent; Guinchard, Xavier; Vincent, Guillaume

doi: 10.1002/anie.202204400pmid: 35570713

The direct dearomative addition of arenes to the C3 position of unprotected indoles is reported under operationally simple conditions, using triflic acid at room temperature. The present regioselective hydroarylation is a straightforward manner to generate an electrophilic indole at the C3 position from unbiased indoles in sharp contrast to previous strategies. This atom‐economical method delivers biologically relevant 3‐arylindolines and 3,3‐spiroindolines in high yields and regioselectivities from both intra‐ and intermolecular processes. DFT computations suggest the stabilization of cationic or dicationic intermediates with H‐bonded (TfOH)n clusters.

Schmid, Julian; Wang, Meng; Gutiérrez, Oliver Y.; Bullock, R. Morris; Camaioni, Donald M.; Lercher, Johannes A.

doi: 10.1002/anie.202203172pmid: 35482977

Hydrogenolysis and hydrolysis of aryl ethers in the liquid phase are important reactions for accessing functionalized cyclic compounds from renewable feedstocks. On supported noble metals, hydrogenolysis is initiated by a hydrogen addition to the aromatic ring followed by C−O bond cleavage. In water, hydrolysis and hydrogenolysis proceed by partial hydrogenation of the aromatic ring prior to water or hydrogen insertion. The mechanisms are common for the studied metals, but the selectivity to hydrogenolysis increases in the order Pd<Rh<Ir<Ru≈Pt in decalin and water; the inverse was observed for the selectivity to hydrolysis in water. Hydrogenolysis selectivity correlates with the Gibbs free energy of hydrogen adsorption. Hydrogenolysis has the highest standard free energy of activation and a weak dependence on H2 pressure, thus, the selectivity to hydrogenolysis is maximized by increasing temperature and decreasing H2 pressure. Selectivity to C−O bond cleavage reaches >95 % in water and alkaline conditions.

Sander, Stefan; Braun, Thomas

doi: 10.1002/anie.202204678pmid: 35420731

The reaction of the Pt complexes cis‐[Pt(CH3)2{R2P(Ind)}2] (Ind=2‐(3‐methyl)indolyl, R=Ph (1 a), 4‐FC6H4 (1 b), 4‐CF3C6H4 (1 c)) with HF afforded the fluorido complexes trans‐[Pt(F(HF)2)(CH3){R2P(Ind)}2] 2 a–c, which can be converted into trans‐[Pt(F)(CH3){R2P(Ind)}2] (3 a–c) by treatment with CsF. Addition of 3‐hexyne to 2 a–c gave alkyne complexes trans‐[Pt(C,C‐η2‐C2H5C≡CC2H5)(CH3){R2P(Ind)}2{F(HF)2}] (4 a–c) at which a fluoride is stabilised as polyfluoride in the coordination sphere by hydrogen bonding to the indolyl‐substituted phosphine ligands. Subsequent heating of a solution of 4 a in the presence of PVPHF led to fluoroalkene formation. Selective catalytic hydrofluorination of alkynes to yield (Z)‐fluoroalkenes were developed. The ability of hydrogen bonding to polyfluoride favours the fluorination step as demonstrated by studies with complexes bearing no indolyl groups at the phosphine ligands.

Ni, Lin; Yu, Chang; Wei, Qianbing; Liu, Dongming; Qiu, Jieshan

doi: 10.1002/anie.202115885pmid: 35524649

Pickering emulsions are particle‐stabilized surfactant‐free dispersions composed of two immiscible liquid phases, and emerge as attractive catalysis platform to surpass traditional technique barrier in some cases. In this review, we have comprehensively summarized the development and the catalysis applications of Pickering emulsions since the pioneering work in 2010. The explicit mechanism for Pickering emulsions will be initially discussed and clarified. Then, summarization is given to the design strategy of amphiphilic emulsion catalysts in two categories of intrinsic and extrinsic amphiphilicity. The progress of the unconventional catalytic reactions in Pickering emulsion is further described, especially for the polarity/solubility difference‐driven phase segregation, “smart” emulsion reaction system, continuous flow catalysis, and Pickering interfacial biocatalysis. Challenges and future trends for the development of Pickering emulsion catalysis are finally outlined.

Guo, Yuan; Han, Guangchao; Yi, Yuanping

doi: 10.1002/anie.202205975pmid: 35604363

The A‐DA′D‐A fused‐ring electron acceptors with an angular fusion mode and electron‐deficient core has significantly boosted organic photovoltaic efficiency. Here, the intrinsic role of the peculiar structure is revealed by comparing representative A‐DA′D‐A acceptor Y6 with its A‐D‐A counterparts having different fusion modes. Owing to the more delocalized HOMO and deeper LUMO level, Y6 exhibits stronger and red‐shifted absorption relative to the linear and angular fused A‐D‐A acceptors, respectively. Moreover, the change from linear to angular fusion substantially reduces the electron‐vibration couplings, which is responsible for the faster exciton diffusion, exciton dissociation, and electron transport for Y6 than the linear fused A‐D‐A acceptor. Notably, the electron‐vibration coupling for exciton dissociation is further decreased by introducing the electron‐deficient core, thus contributing to the efficient charge generation under low driving forces in the Y6‐based devices.

Zhou, Xunzhu; Zhang, Qiu; Zhu, Zhuo; Cai, Yichao; Li, Haixia; Li, Fujun

doi: 10.1002/anie.202205045pmid: 35533111

Metallic Na is a promising anode for rechargeable batteries, however, it is plagued by an unstable solid electrolyte interphase (SEI) and Na dendrites. Herein, a robust anion‐derived SEI is constructed on Na anode in a high‐concentration 1,2‐dimethoxyethane (DME) based electrolyte with a cosolvent hydrofluoroether, which effectively restrains Na dendrite growth. The hydrofluoroether can tune the solvation configuration of the electrolyte from three‐dimensional network aggregates to solvent–cation–anion clusters, enabling more anions to enter and reinforce the inner solvation sheath and their stepwise decomposition. The gradient inorganic‐rich SEI leads to a reduced energy barrier of Na+ migration and enhanced interfacial kinetics. These render the Na||Na3V2(PO4)3 battery with an excellent rate capability of 79.9 mAh g−1 at 24 C and a high capacity retention of 94.2 % after 6000 cycles at 2 C. This highlights the modulation of the electrode–electrolyte interphase chemistry for advanced batteries.