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In this paper, the unconventional light‐matter interactions between giant atoms and structured baths (i.e., lattices) are studied with either Hermitian or non‐Hermitian next‐nearest‐neighbor coupling terms. Essentially different dynamics of the atoms and the propagating field in the Hermitian and non‐Hermitian cases is revealed, which can be further engineered by tuning parameters such as the atomic transition frequency and the (synthetic) magnetic field associated to the coupling terms. The next‐nearest‐neighbor couplings play an important role in controlling the emission direction and the field distribution in the lattice, thus providing opportunities for tailoring exotic dipole–dipole interactions. The results in this paper have potential applications in, e.g., engineering unconventional quantum networks and simulating quantum many‐body systems. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the boundedness of mixed Journé's class operators on weighted multi‐parameter mixed Hardy spaces via atoms decomposition. Moreover, we give a specific singular integral operator in mixed Journé's class which has better properties. [ABSTRACT FROM AUTHOR]

Atom transfer radical addition (ATRA) of halogenated compounds with alkenes is well established but primary alkyl chlorides are understudied because of the difficult C−Cl bond activation. In this paper, we show that TONs of 61 can be achieved in the ATRA of ethyl chloroacetate onto styrene with [Cp*Ru(Cl)2(PPh3)] and 1,1′‐azobis(cyclohexanecarbonitrile) (ACHN) as a radical initiator, representing a three‐fold improvement compared to previous reports. New catalyst precursors of the type [Cp*Ru(Cl)2(PR3)] were synthesized and tested (R=Me, Et, Cy, Ph, p‐CF3C6H4 and p‐MeOC6H4). The kinetic reaction profiles were studied using in situ ATR−FTIR spectroscopy. Among these complexes, [Cp*Ru(Cl)2(PPh3)] gave the best yields while [Cp*Ru(Cl)2(PMe3)] showed the highest rate. While rates correlate with redox potentials (electronics), our investigation reveals that substrate sterics are important for the overall yield. Density functional theory calculations suggest an open‐shell singlet pathway, where polymerization is kinetically disfavored, explaining the selectivity towards ATRA products. [ABSTRACT FROM AUTHOR]

In this paper, conventional phonon blockade (CPNB) and conventional photon blockade (CPTB) effects, as well as unconventional phonon blockade (UPB) effects, are studied in an optomechanical system with nonlinear interaction between the cavity frequency and the square of the mechanical displacement driven by an external field, where a two‐level atom couples with the mechanical mode and a microwave driving field pumps cavity mode. The second‐order correlation function is analytically calculated, which is in good agreement with the numerical simulation given by the master equation. With energy‐level diagram, the atom‐mechanical mode coupling is found to induces the degeneracy splitting of the states and give the optimal conditions for CPNB and CPTB in this system. With the origin of UPB, the optimal conditions are derived and it is found that the realization of UPB is determined by the two couplings of the cavity and atom with respect to the mechanical mode. Moreover, some discussions on the experimental implementation in this quadratically coupled optomechanical system are presented. This study provides a possible way for realizing single‐photon nonlinearity and can extend the applications of optomechanical systems in the field of quantum optics. [ABSTRACT FROM AUTHOR]

Luminescent cuprous complexes are an important class of coordination compounds due to their relative abundance, low cost and ability to display excellent luminescence. The title heteroleptic cuprous complex, [2,2′‐bis(diphenylphosphanyl)‐1,1′‐binaphthyl‐κ2P,P′](2‐phenylpyridine‐κN)copper(I) hexafluoridophosphate, rac‐[Cu(C44H32P2)(C11H9N)]PF6, conventionally abbreviated rac‐[Cu(BINAP)(2‐PhPy)]PF6 (I), where BINAP and 2‐PhPy represent 2,2′‐bis(diphenylphosphanyl)‐1,1′‐binaphthyl and 2‐phenylpyridine, respectively, is described. In this complex, the asymmetric unit consists of a hexafluoridophosphate anion and a heteroleptic cuprous complex cation, in which the cuprous centre in a CuP2N coordination triangle is coordinated by two P atoms from the BINAP ligand and by one N atom from the 2‐PhPy ligand. Time‐dependent density functional theory (TD–DFT) calculations show that the UV–Vis absorption of I should be attributed to ligand‐to‐ligand charge transfer (LLCT) characteristic excited states. It was also found that the paper‐based film of this complex exhibited obvious luminescence light‐up sensing for pyridine. [ABSTRACT FROM AUTHOR]

The synthesis of polycyclic γ‐ and δ‐lactams bearing up to four contiguous fully controlled stereocenters is presented. For that purpose, we developed an original approach based on the use of 2,3‐epoxyamides in domino reactions by taking advantage of the nucleophilic nitrogen atom and electrophilic epoxide. In reaction with enol ethers bearing gem bis‐electrophiles on the double bond as Michael acceptors, four different reaction pathways were observed. They all started with a domino oxa‐Michael/aza‐Michael/epoxide opening sequence and depending on substrates engaged could be followed either by a lactonization or a hemiketalization/retro‐aldol cascade. Thus, four original fully‐substituted piperidine‐ or pyrrolidine‐2‐one scaffolds were selectively synthesized in good to high yields. Moreover, these polycyclic lactams were obtained in high stereo‐ and chemo‐selectively highlighting the efficiency and molecular diversity offered by this new methodology that should offer various synthetic opportunities in the future. [ABSTRACT FROM AUTHOR]

Single atomic catalysts have shown great potential in efficiently electro‐converting O2 to H2O2 with high selectivity. However, the impact of coordination environment and introduction of extra metallic aggregates on catalytic performance still remains unclear. Herein, first a series of carbon‐based catalysts with embedded coupling Ni single atomic sites and corresponding metallic nanoparticles at adjacent geometry is synthesized. Careful performance evaluation reveals NiSA/NiNP‐NSCNT catalyst with precisely controlled active centers of synergetic adjacent Ni‐N4S single sites and crystalline Ni nanoparticles exhibits a high H2O2 selectivity over 92.7% within a wide potential range (maximum selectivity can reach 98.4%). Theoretical studies uncover that spatially coupling single atomic NiN4S sites with metallic Ni aggregates in close proximity can optimize the adsorption behavior of key intermediates *OOH to achieve a nearly ideal binding strength, which thus affording a kinetically favorable pathway for H2O2 production. This strategy of manipulating the interaction between single atoms and metallic aggregates offers a promising direction to design new high‐performance catalysts for practical H2O2 electrosynthesis. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) are widely regarded as promising next‐generation batteries due to their high theoretical specific capacity and low material cost. However, the practical applications of LSBs are limited by the shuttle effect of lithium polysulfides (LiPSs), electronic insulation of charge and discharge products, and slow LiPSs conversion reaction kinetics. Accordingly, the introduction of catalysts into LSBs is one of the effective strategy to solve the issues of the sluggished LiPS conversion. Because of their nearly 100% atom utilization and high electrocatalytic activity, single‐atom catalysts (SACs) have been widely used as reaction mediators for LSBs' reactions. Excitingly, the SACs with asymmetric coordination structures have exhibited intriguing electronic structures and superior catalytic activities when compared to the traditional M–N4 active sites. In this review, we systematically describe the recent advancements in the installation of asymmetrically coordinated single‐atom structure as reactions catalysts in LSBs, including asymmetrically nitrogen coordinated SACs, heteroatom coordinated SACs, support effective asymmetrically coordinated SACs, and bimetallic coordinated SACs. Particularly noteworthy is the discussion of the catalytic conversion mechanism of LiPSs spanning asymmetrically coordinated SACs. Finally, a perspective on the future developments of asymmetrically coordinated SACs in LSB applications is provided. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a vital chemical for modern human society. It is conventionally produced by the energy‐ and emission‐intensive Haber–Bosch process. Alternatively, sustainable NH3 production from renewable electricity‐driven electrolyzers has emerged as a promising route. Particularly, NH3 synthesis from nitrate (NO3−), a common pollutant in water and soil, by the nitrate reduction reaction (NO3RR) has drawn wide attention. Among various catalysts demonstrated recently, copper (Cu)‐based catalysts have been recognized as attractive candidates due to their availability, good activity, high NH3 selectivity, and facile reaction kinetics. In this review, the recent progress of Cu‐based NO3RR catalysts from the reaction mechanistic fundamentals to various catalyst design strategies, aiming at providing an on‐time summary, is summarized, and perspectives that can guide the rational and on‐demand design of Cu‐ and other earth‐abundant metal‐based catalysts for selective NO3RR toward sustainable NH3 production are elucidated. [ABSTRACT FROM AUTHOR]

Rationale: The observed isotope distribution is an important attribute for the identification of peptides and proteins in mass spectrometry-based proteomics. Sulphur atoms have a very distinctive elemental isotope definition, and therefore, the presence of sulphur atoms has a substantial effect on the isotope distribution of biomolecules. Hence, knowledge of the number of sulphur atoms can improve the identification of peptides and proteins. Methods: In this paper, we conducted a theoretical investigation on the isotope properties of sulphur-containing peptides. We proposed a gradient boosting approach to predict the number of sulphur atoms based on the aggregated isotope distribution. We compared prediction accuracy and assessed the predictive power of the features using the mass and isotope abundance information from the first three, five and eight aggregated isotope peaks. Results: Mass features alone are not sufficient to accurately predict the number of sulphur atoms. However, we reach near-perfect prediction when we include isotope abundance features. The abundance ratios of the eighth and the seventh, the fifth and the fourth, and the third and the second aggregated isotope peaks are the most important abundance features. The mass difference between the eighth, the fifth or the third aggregated isotope peaks and the monoisotopic peak are the most predictive mass features. Conclusions: Based on the validation analysis it can be concluded that the prediction of the number of sulphur atoms based on the isotope profile fails, because the isotope ratios are not measured accurately. These results indicate that it is valuable for future instrument developments to focus more on improving spectral accuracy to measure peak intensities of higher-order isotope peaks more accurately. [ABSTRACT FROM AUTHOR]

In this paper, a robust and accurate protocol is proposed to realize nondestructive parity measurement of artificial atoms using a superconducting resonator and homodyne measurement. With the help of an additional microwave driving field, the cavity field evolves into a coherent state or remains in a vacuum state according to the parity of the atoms. Consequently, the parity information of atoms can be read out by a homodyne measurement on the cavity. Parity information can be obtained without destroying the original state of the system, which means that the state can be further applied to other quantum information processing tasks after a parity measurement. The numerical simulation results show that the protocol is robust against systematic error, random noise, and decoherence. Therefore, this protocol can provide a feasible viewpoint for nondestructive parity measurement. [ABSTRACT FROM AUTHOR]

In this paper, the atomic configuration, electronic structure, and work of adhesion for TiN(111)//B2‐NiTi(110) and TiN(111)//B19′‐NiTi(010) interfaces were investigated by first‐principles calculations based on density functional theory (DFT), which aim to provide a theoretical guidance for analyzing the service reliability of TiN films modified NiTi alloy devices. The results of this paper indicated that a hollow‐site stacking structure was formed on the interface when Ti and N were the terminal atoms on two sides. Such interfaces demonstrated a stronger bonding performance and a more stable structure than that with Ni and Ti as the terminal atoms. The work of adhesion of the TiN(111)//B19′‐NiTi(010) interface was 17.47 J/m2, which is greater than the work of fracture of TiN(111) (6.73 J/m2), whereas the work of adhesion of the TiN(111)//B2‐NiTi(110) interface was found to reach 5.49 J/m2, which is lower than the work of fracture of TiN(111). The models of the work of adhesion between the two interfaces indicate that there are significant bond strength changes in the TiN/NiTi interface, when the NiTi substrate undergoes martensitic transformation. The results of this paper contribute significantly to the service reliability analysis of TiN films coated on NiTi alloy devices. [ABSTRACT FROM AUTHOR]

Chaos is important in nonlinear science and promotes the development of fundamental studies, such as neural networks, extreme event statistics, and electron transport. In this paper, a theoretical scheme for generating dynamical chaos in a Fabry–Perot cavity with two‐level atoms is investigated. Through the injection of atoms, controllable chaos of the cavity and mechanical oscillator is achieved simultaneously by the external laser field. The trajectory and the maximal Lyapunov exponent that characterize the properties of the chaos could be optimized by adjusting the coupling constant, driving field, injection of atoms, the frequency of the cavity, and the frequency of the mechanical oscillator. This study provides a new idea to manipulate the cavity and mechanical chaos assisted by two level atoms. It is hoped that the results presented can benefit controllable chaos generation and its applications. [ABSTRACT FROM AUTHOR]

This paper investigates the dynamics of two two‐level atoms, which simultaneously couple to a quasi‐1D waveguide with rectangular cross section. The waveguide modes serve as environment, which induces the interaction and collective dissipation between the two distant atoms. When both of the two atoms are located in the middle of the waveguide, a retardation effect is observed, which can be broken by moving one of the atoms away from the center of the waveguide. To preserve the complete dissipation of the system via dark state mechanism, a scheme where the connection of the atoms is perpendicular to the axis of the waveguide is proposed. [ABSTRACT FROM AUTHOR]

Midlatitude ionosonde observations show that there is a sporadic E (Es) diurnal cycle that starts in higher altitudes at sunrise. This property is labeled as the "Sporadic E sunrise effect." Given that sporadic E layers are composed of metal ions, the sunrise effect implies that metal atom solar photoionization could play a role in the diurnal variability of sporadic E occurrence. This possibility is endorsed by Arecibo's incoherent scatter radar observations, showing that weak ion layers at lowest E and uppermost D region heights appear at sunrise to live during the daytime, apparently coming out of nighttime metal atom mesospheric layers. The solar photoionization of metal atoms increases the abundance of metal ions available for Es layer generation during the daytime, whereas this effect is absent at nighttime. This can explain why sporadic E layers start or intensify at sunrise all year round and why Es activity maximizes during sunlit hours, as has been reported in many ionosonde and satellite radio occultation studies. The significance of metal atom solar photoionization on the regular diurnal variation of Es went unnoticed, despite existing evidence for a long time. The present paper provides a base for a better physical understanding of the pronounced 24-hr periodicity in Es layer intensity and places a step toward the improvement of simulation models for the predictions of sporadic E layer characteristics. [ABSTRACT FROM AUTHOR]

Nonconventional luminescent materials have been rising stars in organic luminophores due to their intrinsic characteristics, including water‐solubility, biocompatibility, and environmental friendliness and have shown potential applications in diverse fields. As an indispensable branch of nonconventional luminescent materials, polysiloxanes, which consist of electron‐rich auxochromic groups, have exhibited outstanding photophysical properties due to the unique silicon atoms. The flexible Si‐O bonds benefit the aggregation, and the empty 3d orbitals of Si atoms can generate coordination bonds including N → Si and O → Si, altering the electron delocalization of the material and improving the luminescent purity. Herein, we review the recent progress in luminescent polysiloxanes with different topologies and discuss the challenges and perspectives. With an emphasis on the driving force for the aggregation and the mechanism of tuned emissions, the role of Si atoms played in the nonconventional luminophores is highlighted. This review may provide new insights into the design of nonconventional luminescent materials and expand their further applications in sensing, biomedicine, lighting devices, etc. [ABSTRACT FROM AUTHOR]

The X‐ray constrained wavefunction (XCW) procedure for obtaining an experimentally reconstructed wavefunction from X‐ray diffraction data is reviewed. The two‐center probability distribution model used to perform nuclear‐position averaging in the original paper [Grimwood & Jayatilaka (2001). Acta Cryst. A57, 87–100] is carefully distinguished from the newer one‐center probability distribution model. In the one‐center model, Hirshfeld atoms are used, and the Hirshfeld atom based X‐ray constrained wavefunction (HA‐XCW) procedure is described for the first time, as well as its efficient implementation. In this context, the definition of the related X‐ray wavefunction refinement (XWR) method is refined. The key halting problem for the XCW method – the procedure by which one determines when overfitting has occurred – is named and work on it reviewed. [ABSTRACT FROM AUTHOR]

Nitrogenase is the enzyme that converts N2 to NH3 under ambient conditions. The chemical mechanism of this catalysis at the active site FeMo‐co [Fe7S9CMo(homocitrate)] is unknown. An obligatory co‐product is H2, while exogenous H2 is a competitive inhibitor. Isotopic substitution using exogenous D2 revealed the N2‐dependent reaction D2+2H++2e−→2HD (the 'HD reaction'), together with a collection of additional experimental characteristics and requirements. This paper describes a detailed mechanism for the HD reaction, developed and elaborated using density functional simulations with a 486‐atom model of the active site and surrounding protein. First D2 binds at one Fe atom (endo‐Fe6 coordination position), where it is flanked by H−Fe6 (exo position) and H−Fe2 (endo position). Then there is synchronous transfer of these two H atoms to bound D2, forming one HD bound to Fe2 and a second HD bound to Fe6. These two HD dissociate sequentially. The final phase is recovery of the two flanking H atoms. These H atoms are generated, sequentially, by translocation of a proton from the protein surface to S3B of FeMo‐co and combination with introduced electrons. The first H atom migrates from S3B to exo‐Fe6 and the second from S3B to endo‐Fe2. Reaction energies and kinetic barriers are reported for all steps. This mechanism accounts for the experimental data: (a) stoichiometry; (b) the N2‐dependence results from promotional N2 bound at exo‐Fe2; (c) different N2 binding Km for the HD reaction and the NH3 formation reaction results from involvement of two different sites; (d) inhibition by CO; (e) the non‐occurrence of 2HD→H2+D2 results from the synchronicity of the two transfers of H to D2; (f) inhibition of HD production at high pN2 is by competitive binding of N2 at endo‐Fe6; (g) the non‐leakage of D to solvent follows from the hydrophobic environment and irreversibility of proton introduction. [ABSTRACT FROM AUTHOR]

Nanozymes have received extensive attention in the fields of sensing and detection, medical therapy, industry, and agriculture thanks to the combination of the catalytic properties of natural enzymes and the physicochemical properties of nanomaterials, coupled with superior stability and ease of preparation. Despite the promise of nanozymes, conventional nanozymes are constrained by their oversized size and low catalytic capacity in sophisticated practical application environments. single‐atom nanozymes (SAzymes) were characterized as nanozymes with high catalytic efficiency by uniformly distributed single atoms as catalysis sites, thus effectively addressing the defects of conventional nanozymes. This paper reviews the activity improvement scheme and catalytic mechanism of SAzymes and highlights the latest research progress of SAzymes in the fields of biomedical sensing and therapy. Eventually, the challenges and future directions of SAzymes are discussed in this paper. [ABSTRACT FROM AUTHOR]

The relativistic effects have been widely reported to affect the chemical and physical properties of the heavy elements such as lanthanides (57≤z≤71), actinides (89≤z≤103), and transactinides (z≥104). This effect is definitely weakened by reducing the atomic number z in lighter elements such as hydrogen‐like atoms (HLAs). The aim of present paper is to investigate the relativistic effects of electron motion in Bohr orbits on the chemical and physical properties of HLAs. The theoretical model is based on the Heisenberg (rather than Schrodinger) picture where the relativistic vibrational Hamiltonian (RVH) Hvibrel is expanded as a power series of harmonic oscillator Hamiltonian H0 for the first time. By applying the first‐order RVH (correct to H0) to the Heisenberg equation, a pair of coupled equations is obtained for the relativistic position and linear momentum of electron. A simple comparison of the first‐order relativistic and nonrelativistic equations reveals that the relativistic natural frequency of an HLA (like entropy) is slowly raised by increasing z beyond z≈20. In general, RVH plays a fundamental role because it specifies the temporal relativistic variations of position, velocity, and linear momentum of the oscillating electron. The results are finally verified by demonstrating energy conservation. [ABSTRACT FROM AUTHOR]

This paper analyzes a common‐value, first‐price auction with state‐dependent participation. The number of bidders, which is unobservable to them, depends on the true value. For participation patterns with many bidders in each state, the bidding equilibrium may be of a "pooling" type—with high probability, the winning bid is the same across states and is below the ex ante expected value—or of a "partially revealing" type—with no significant atoms in the winning bid distribution and an expected winning bid increasing in the true value. Which of these forms will arise is determined by the likelihood ratio at the top of the signal distribution and the participation across states. We fully characterize this relation and show how the participation pattern determines the extent of information aggregation by the price. [ABSTRACT FROM AUTHOR]

Tuning the coordination structures of metal sites is intensively studied to improve the performances of single‐atom site catalysts (SASC). However, the pore structure of SASC, which is highly related to the accessibility of active sites, has received little attention. In this work, single‐atom ZnN4 sites embedded in P‐functionalized carbon with hollow‐wall and 3D ordered macroporous structure (denoted as H‐3DOM‐ZnN4/P‐C) are constructed. The creation of hollow walls in ordered macroporous structures can largely increase the external surface area to expose more active sites. The introduction of adjacent P atoms can optimize the electronic structure of ZnN4 sites through long‐rang regulation to enhance the intrinsic activity and selectivity. In the electrochemical CO2 reduction reaction, H‐3DOM‐ZnN4/P‐C exhibits high CO Faradaic efficiency over 90% in a wide potential window (500 mV) and a large turnover frequency up to 7.8 × 104 h−1 at −1.0 V versus reversible hydrogen electrode, much higher than its counterparts without the hierarchically ordered structure or P‐functionalization. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) production by the electrochemical 2‐electron oxygen reduction reaction (2e− ORR) is a promising alternative to the energy‐intensive anthraquinone process, and single‐atom electrocatalysts show the unique capability of high selectivity toward 2e− ORR against the 4e− one. The extremely low surface density of the single‐atom sites and the inflexibility in manipulating their geometric/electronic configurations, however, compromise the H2O2 yield and impede further performance enhancement. Herein, we construct a family of multiatom catalysts (MACs), on which two or three single atoms are closely coordinated to form high‐density active sites that are versatile in their atomic configurations for optimal adsorption of essential *OOH species. Among them, the Cox–Ni MAC presents excellent electrocatalytic performance for 2e− ORR, in terms of its exceptionally high H2O2 yield in acidic electrolytes (28.96 mol L−1 gcat.−1 h−1) and high selectivity under acidic to neutral conditions in a wide potential region (>80%, 0–0.7 V). Operando X‐ray absorption and density functional theory analyses jointly unveil its unique trimetallic Co2NiN8 configuration, which efficiently induces an appropriate Ni–d orbital filling and modulates the *OOH adsorption, together boosting the electrocatalytic 2e− ORR capability. This work thus provides a new MAC strategy for tuning the geometric/electronic structure of active sites for 2e− ORR and other potential electrochemical processes. [ABSTRACT FROM AUTHOR]

Interaction of atoms with twisted light is the subject of intense experimental and theoretical investigation. In almost all studies, the atom is viewed as a localized probe of the twisted light field. However, as argued in this paper, conceptually novel effects will arise if light‐atom interaction is studied in the double‐twisted regime with delocalized atoms, that is, either via twisted light absorption by atom vortex beam, or via two‐twisted‐photon spectroscopy of atoms in a non‐vortex but delocalized state. Even for monochromatic twisted photons and for an infinitely narrow line, absorption will occur over a finite range of detuning. Inside this range, a rapidly varying absorption probability is predicted, revealing interference fringes induced by two distinct paths leading to the same final state. The number, location, height, and contrast of these fringes can give additional information on the excitation process which would not be accessible in usual spectroscopic settings. Visibility of the predicted effects will be enhanced at the future Gamma factory thanks to the large momenta of ions. [ABSTRACT FROM AUTHOR]

In this first of a series of publications, the X‐ray scattering factors for neutral atoms are revisited. Using the recently developed DBSR_HF program [Zatsarinny & Froese Fischer (2016). Comput. Phys. Comm.202, 287–303] the fully relativistic Dirac–Hartree–Fock ground‐state wavefunctions for all atoms with Z = 2–118 (He–Og) have been calculated using the extended average level scheme and including both the Breit interaction correction to the electronic motion due to magnetic and retardation effects, and the Fermi distribution function for the description of the nuclear charge density. The comparison of our wavefunctions with those obtained in several previous studies in terms of the total and orbital (spinor) electronic energies, and a number of local and integrated total and orbital properties, confirmed the quality of the generated wavefunctions. The employed dense radial grid combined with the DBSR_HF's B‐spline representation of the relativistic one‐electron orbitals allowed for a precise integration of the X‐ray scattering factors using a newly developed Fortran program SF. Following the established procedure [Maslen et al. (2006). International Tables for Crystallography, Vol. C, Section 6.1.1, pp. 554–589], the resulting X‐ray scattering factors have been interpolated in the 0 ≤ sin θ/λ ≤ 2 Å−1 and 2 ≤ sin θ/λ ≤ 6 Å−1 ranges using the recommended analytical functions with both the four‐ (which is a current convention) and five‐term expansions. An exhaustive comparison of the newly generated X‐ray scattering factors with the International Union of Crystallography recommended values and those from a number of previous studies showed an overall good agreement and allowed identification of a number of typos and inconsistencies in the recommended quantities. A detailed analysis of the results suggests that the newly derived values may represent an excellent compromise among all the previous studies. The determined conventional interpolating functions for the two sin θ/λ intervals show, on average, the same accuracy as the recommended parametrizations. However, an extension of each expansion by only a single term provides a significant improvement in the accuracy of the interpolated values for an overwhelming majority of the atoms. As such, an updated set of the fully relativistic X‐ray scattering factors and the interpolating functions for neutral atoms with Z = 2–118 can be easily incorporated into the existing X‐ray diffraction software with only minor modifications. The outcomes of the undertaken research should be of interest to members of the crystallographic community who push the boundaries of the accuracy and precision of X‐ray diffraction studies. [ABSTRACT FROM AUTHOR]

Nano‐carbon oxygen reduction reaction (ORR) catalyst having a large N atoms content derived from biomass has been widely studied recently in fuel cells. In this paper, yuba of high‐protein (wt. 53 %) was employed as precursor to fabricate N self‐doped porous carbon ORR electrocatalysts with high N content. In terms of ORR performance, Y‐850 exhibited the optimal electrocatalytic activity among all the samples at different pyrolysis temperatures, which is comparable that of commercial 20 % Pt/C. The prominent ORR characteristic of Y‐850 is mainly contributed by its high N content, especially high graphitic‐N content. In order to further improve its ORR performance, ball‐milling was conducted on Y‐850 before and after pyrolysis. The results indicate that an appropriate ball‐milling before pyrolysis can effectively increase the limited current density of ORR. [ABSTRACT FROM AUTHOR]

Graphyne (GY) is an allotrope composed of sp and sp2 hybridized carbon atoms. In this paper, the adsorption performance of Ti‐modified GY (Ti‐GY) system on the adsorption of CH4 molecules is studied based on first principles. The study found that the most stable adsorption site for Ti atoms is the six‐membered carbon ring pore site. There is a strong ionic interaction between the two, and the Ti‐GY system structure remains stable during the adsorption of CH4 molecules. A single Ti‐modified GY can adsorb 7 CH4 molecules on one side, and the adsorption structure is stratified, with average adsorption energy of −0.298 eV, and an adsorption capacity of 0.369 g g−1; two Ti‐modified GY adsorbs 14 CH4 molecules on double‐sided, the average adsorption energy is about −0.300 eV, and the adsorption capacity reaches 0.484 g g−1. The first layer of CH4 molecules is adsorbed, which is mainly affected by the Ti atoms. There is a strong Coulomb interaction between it and Ti. With the increase of CH4 molecules, the adsorption energy decreases; While the second layer of CH4 molecules is due to the distance Ti atoms are far away, At this time, the interaction between the CH4 molecules and the substrate is mainly the electrostatic interaction between the positively charged CH4 molecules and the negatively charged GY and the van der Waals interaction between the CH4 molecules. The adsorption performance of CH4 molecules is closely related to the pore size of the two‐dimensional adsorbent. When the pore size is small, the interaction between molecules is enhanced and the average adsorption energy is larger. On the contrary, the larger the pore size, the higher the adsorption capacity. [ABSTRACT FROM AUTHOR]

BePhX1.91.9-0.3THFBePhX vs. Keywords: beryllium; Grignard compounds; ligand exchange; organometallics; Schlenk equilibrium EN beryllium Grignard compounds ligand exchange organometallics Schlenk equilibrium 1 13 13 10/31/23 20231026 NES 231026 B The reaction of homoleptic beryllium halide b with diphenyl beryllium complexes leads to the clean formation of heteroleptic beryllium I Grignard i compounds [(L) SB 1-2 sb BePh I X i ] SB 1-2 sb ( I X i =Cl, Br, I; L= I C i -, I N i -, I O i -donor ligand). BePhX7.12.91.7NEt3BePhX vs. [Extracted from the article]

Dual‐atom catalysts (DACs) have been a new frontier in heterogeneous catalysis due to their unique intrinsic properties. The synergy between dual atoms provides flexible active sites, promising to enhance performance and even catalyze more complex reactions. However, precisely regulating active site structure and uncovering dual‐atom metal interaction remain grand challenges. In this review, we clarify the significance of the inter‐metal interaction of DACs based on the understanding of active center structures. Three diatomic configurations are elaborated, including isolated dual single‐atom, N/O‐bridged dual‐atom, and direct dual‐metal bonding interaction. Subsequently, the up‐to‐date progress in heterogeneous oxidation reactions, hydrogenation/dehydrogenation reactions, electrocatalytic reactions, and photocatalytic reactions are summarized. The structure‐activity relationship between DACs and catalytic performance is then discussed at an atomic level. Finally, the challenges and future directions to engineer the structure of DACs are discussed. This review will offer new prospects for the rational design of efficient DACs toward heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Dual‐atom catalysts (DACs) have been a new frontier in heterogeneous catalysis due to their unique intrinsic properties. The synergy between dual atoms provides flexible active sites, promising to enhance performance and even catalyze more complex reactions. However, precisely regulating active site structure and uncovering dual‐atom metal interaction remain grand challenges. In this review, we clarify the significance of the inter‐metal interaction of DACs based on the understanding of active center structures. Three diatomic configurations are elaborated, including isolated dual single‐atom, N/O‐bridged dual‐atom, and direct dual‐metal bonding interaction. Subsequently, the up‐to‐date progress in heterogeneous oxidation reactions, hydrogenation/dehydrogenation reactions, electrocatalytic reactions, and photocatalytic reactions are summarized. The structure‐activity relationship between DACs and catalytic performance is then discussed at an atomic level. Finally, the challenges and future directions to engineer the structure of DACs are discussed. This review will offer new prospects for the rational design of efficient DACs toward heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Designing reasonable atomic structures is essential in modulating the selectivity of the valuable products produced in the electrochemical CO2 reduction. Herein, a CuSn diatomic sites electrocatalyst stabilized by double oxygen vacancies on CeO2‐x is constructed, which exhibits superior electrochemical selectivity toward formate, achieving a 90.0% Faradaic efficiency at formate partial current density of 216.8 mA cm−2 with the applied bias of −1.2 V versus REH. The experimental characterizations and theoretical calculations highlight the significance of the synergistic effect of Cu and Sn diatoms on reducing the activation energy and promoting the formation of intermediate *OCHO, which accounts for its high selectivity toward formate. Meanwhile, the oxygen vacancies on the CeO2‐x also play a pivotal role in manipulating the electrochemical performance and stability, which underlines the importance of regulating the electronic metal‐support interaction between CuSn diatoms and CeO2‐x. This work demonstrates an effective method to design efficient electrochemical CO2 reduction catalysts by modulating the surface structures of single‐atoms anchored support. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (CO2RR) to value‐added chemicals with renewable electricity is a promising method to decarbonize parts of the chemical industry. Recently, single metal atoms in nitrogen‐doped carbon (MNC) have emerged as potential electrocatalysts for CO2RR to CO with high activity and faradaic efficiency, although the reaction limitation for CO2RR to CO is unclear. To understand the comparison of intrinsic activity of different MNCs, two catalysts are synthesized through a decoupled two‐step synthesis approach of high temperature pyrolysis and low temperature metalation (Fe or Ni). The highly meso‐porous structure results in the highest reported electrochemical active site utilization based on in situ nitrite stripping; up to 59±6% for NiNC. Ex situ X‐ray absorption spectroscopy (XAS) confirms the penta‐coordinated nature of the active sites. The catalysts are amongst the most active in the literature for CO2 reduction to CO. The density functional theory calculations (DFT) show that their binding to the reaction intermediates approximates to that of Au surfaces. However, it is found that the turnover frequencies (TOFs) of the most active catalysts for CO evolution converge, suggesting a fundamental ceiling to the catalytic rates. [ABSTRACT FROM AUTHOR]

The description of π‐donor amido moieties as 'weak‐field' ligands can belie the influence of metal‐ligand covalency on the overall ligand field of coordination complexes, which can in turn influence properties including the magnetic ground state and those of their excited states. In this contribution, the ligand fields of pseudo‐octahedral Ni(II) complexes supported by diarylamido pincer‐type amido ligands – three previously reported examples supported by asymmetric (2‐R‐phenanthridin‐4‐yl)(8‐quinolinyl)amido ligands (R = Cl, CF3, tBu; RL1) along with a new congener bearing a symmetric bis(8‐quinolinyl)amido ligand (BQA; L2) – were investigated in two ways. First, high‐frequency and ‐field electron paramagnetic resonance spectroscopy (HFEPR), SQUID magnetometry, and electronic absorption spectroscopy were used to determine the ligand field parameters. Second, the ability to electrochemically address ligand‐based oxidations despite metal‐centered SOMOs in the parent S=1 paramagnets was investigated, supported by time‐dependent density functional theory (TDDFT) identification of strong intervalence charge‐transfer (IVCT) transitions attributed to electronic communication between two Namido moieties mediated by a Ni(II) bridge. These findings are discussed in the broader context of 3d transition metal coordination complexes of weak‐field π‐donor ligands. [ABSTRACT FROM AUTHOR]

This work investigates the temporal dynamics of O atoms in nonequilibrium atmospheric pressure plasma (NAPP) generated by kHz nanosecond pulsed discharge. Two‐photon laser‐induced fluorescence (TALIF) method is used to measure the time resolution of O atom density from the first discharge pulse in two gas mixtures, He + 0.4%O2 and He + 0.4%air. The discharge frequencies of 1 and 10 kHz are considered in the experiment. The results show that the O atom density does not accumulate with increasing number of pulses in both gas environments at 1 kHz. However, at 10 kHz, a cumulative effect of O atom density with the number of pulses is observed in both gas mixtures. After 10 and 300 discharge pulses in He + 0.4%O2 and He + 0.4%air, respectively, the O atom density saturates at the same moment after each discharge cycle. It was found that even after a long operating period of discharge, the decay of O atom density during each discharge cycle is not negligible. The O atom density in He + 0.4%O2 varies in the range of 2.85 × 1021 m−3–4.29 × 1021 m−3 while the O atom density in He + 0.4%air varies in the range of 2.60 × 1021 m−3–3.19 × 1021 m−3. This indicates that the choice of diagnostic time points is important for the O atom density measurements when using TALIF to diagnose kHz pulsed NAPP. In addition, 0D plasma chemical kinetics models are developed for the two gas mixtures to investigate O atoms' production and consumption processes. The causes of the cumulative effect of O atom density at 10 kHz, the saturation effect, and the formation of the periodic variation trend are also investigated. The simulation results show that the consumption rate of O atoms and the O atom density are directly correlated. As the number of pulses increases, the O atom consumption rate increases, which gradually counteracts the number of O atoms generated during the pulse discharge. This leads to delay and saturation of the cumulative effect of O atoms. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of oxygen into hydrogen peroxide in an acidic medium offers an energy‐efficient and green H2O2 synthesis as an alternative to the energy‐intensive anthraquinone process. Unfortunately, high overpotential, low production rates, and fierce competition from traditional four‐electron reduction limit it. In this study, a metalloenzyme‐like active structure is mimicked in carbon‐based single‐atom electrocatalysts for oxygen reduction to H2O2. Using a carbonization strategy, the primary electronic structure of the metal center with nitrogen and oxygen coordination is modulated, followed by epoxy oxygen functionalities close to the metal active sites. In an acidic medium, CoNOC active structures proceed with greater than 98% H2O2 selectivity (2e−/2H+) rather than CoNC active sites that are selective to H2O (4e−/4H+). Among all MNOC (M = Fe, Co, Mn, and Ni) single‐atom electrocatalysts, the CoNOC is the most selective (> 98%) for H2O2 production, with a mass activity of 10 A g−1 at 0.60 V vs. RHE. X‐ray absorption spectroscopy is used to identify the formation of unsymmetrical MNOC active structures. Experimental results are also compared to density functional theory calculations, which revealed that the structure‐activity relationship of the epoxy‐surrounded CoNOC active structure reaches optimum (ΔG*OOH) binding energies for high selectivity. [ABSTRACT FROM AUTHOR]

Aryne insertions into the carbon‐iodine bond of heteroaryl iodides has been achieved for the first time. This novel reaction provides an efficient pathway for the synthesis of valuable building blocks 2‐iodoheterobiaryls from heteroaryl iodides and o‐silylaryl triflates in excellent regioselectivity. The copper(I) catalyst, which bears a N‐heterocyclic carbene (NHC) ligand, is essential to accomplish the reaction. Control reactions and DFT calculations indicate that the coordination of copper, as a Lewis acid, with nitrogen atoms of heteroaryl iodides mediates the insertion of arynes into heteroaryl carbon‐iodine bonds. [ABSTRACT FROM AUTHOR]

Aryne insertions into the carbon‐iodine bond of heteroaryl iodides has been achieved for the first time. This novel reaction provides an efficient pathway for the synthesis of valuable building blocks 2‐iodoheterobiaryls from heteroaryl iodides and o‐silylaryl triflates in excellent regioselectivity. The copper(I) catalyst, which bears a N‐heterocyclic carbene (NHC) ligand, is essential to accomplish the reaction. Control reactions and DFT calculations indicate that the coordination of copper, as a Lewis acid, with nitrogen atoms of heteroaryl iodides mediates the insertion of arynes into heteroaryl carbon‐iodine bonds. [ABSTRACT FROM AUTHOR]

In this study we investigate the pyramidalization of the sp2‐hybridized center at the ipso‐carbon atom Ci of phenyl compounds on the theoretical side by DFT calculations of toluene, t‐butylbenzene, and ethylbenzene and on the experimental side by a scatter plot analysis of 14,169 structures of ethylbenzene compounds Cβ−CαH2−C6H5 with three open positions for variation at Cβ, accumulated in the Cambridge Structural Database. In a 360° rotation about the bond between Cα of the substituent and the ipso‐carbon atom Ci of the phenyl ring, the pyramidalization performs three maxima and minima. A comparison of structures with pyramidalization and its hypothetical counterparts without pyramidalization shows that pyramidalization is associated with a gain of energy. The data reveal that it is the carbon atom Cα of the phenyl substituent, which on pyramidalization bends away from the phenyl plane. Pyramidalization of sp2‐hybridized centers is an omnipresent member in molecular weak interactions. [ABSTRACT FROM AUTHOR]

Precisely regulating the electronic construction of the reactive center is an essential method to improve the electrocatalysis, but achieving efficient multifunctional characteristics remains a challenge. Herein, CoS sample dual‐doped by Cu and F atoms, as bifunctional electrocatalyst, is designed and synthesized for water electrolysis. According to the experimental results, Cu atom doping can perform primary electronic adjustment and obtain bifunctional properties, and then the electronic structure is adjusted for the second time to achieve an optimal state by introducing F atom. Meanwhile, this dual‐doping strategy will result in lattice distortion and expose more active sites. As expected, dual‐doped Cu−F−CoS show the brilliant electrocatalytic activity, revealing ultralow overpotentials (59 mV for HER, 213 mV for OER) at 10 mA cm−2 in alkaline electrolyte. Besides, it also exhibits distinguished water electrolysis activity with cell voltage as low as 1.52 V at 10 mA cm−2. Our work can provide an atomic‐level perception for adjusting the electronic construction of reactive sites by means of dual‐doping engineering and put forward a contributing path for the electrocatalysts with multifunctional designing. [ABSTRACT FROM AUTHOR]

The crotylation reactions of chiral α‐F, α‐OBz and α‐OH aldehydes under Petasis‐borono‐Mannich conditions using (E)‐ or (Z)‐crotylboronates and primary amines resulted in γ‐addition products in high dr and high er. α‐F and α‐OBz aldehydes gave 1,2‐anti‐2,3‐syn and 1,2‐anti‐2,3‐anti, products, respectively while an α‐OH aldehyde gave 1,2‐syn‐2,3‐syn products. The stereochemical outcomes of reactions of the former aldehydes can be explained using a six‐membered ring transition state (TS) model in which a Cornforth‐like conformation around the imine intermediate is favoured resulting in 1,2‐anti products. The 2,3‐stereochemical outcome is dependent upon the geometry of the crotylboronate. These TS models were also supported by DFT calculations. The stereochemical outcomes of reactions employing an α‐OH aldehyde can be rationalised as occurring via an open‐TS involving H‐bonding in the imine intermediate between the α‐OH group and the imine N atom. Representative products were converted to highly functionalized 1,2,3,6‐tetrahydropyridines and 3H‐oxazolo[3,4‐a]pyridine‐3‐ones which will be valuable scaffolds in synthesis. [ABSTRACT FROM AUTHOR]

Metal single atoms (SAs) anchored in carbon support via coordinating with N atoms are efficient active sites to oxygen reduction reaction (ORR). However, rational design of single atom catalysts with highly exposed active sites is challenging and urgently desirable. Herein, an anion exchange strategy is presented to fabricate Fe‐N4 moieties anchored in hierarchical carbon nanoplates composed of hollow carbon spheres (Fe‐SA/N‐HCS). With the coordinating O atoms are substituted by N atoms, Fe SAs with Fe‐O4 configuration are transformed into the ones with Fe‐N4 configuration during the thermal activation process. Insights into the evolution of central atoms demonstrate that the SAs with specific coordination environment can be obtained by modulating in situ anion exchange process. The strategy produces a large quantity of electrochemical accessible site and high utilization rate of Fe‐N4. Fe‐SA/N‐HCS shows excellent ORR electrocatalytic performance with half‐wave potential of 0.91 V (vs. RHE) in 0.1 M KOH, and outstanding performance when used in rechargeable aqueous and flexible Zn‐air batteries. The evolution pathway for SAs demonstrated in this work offers a novel strategy to design SACs with various coordination environment and enhanced electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Metal single atoms (SAs) anchored in carbon support via coordinating with N atoms are efficient active sites to oxygen reduction reaction (ORR). However, rational design of single atom catalysts with highly exposed active sites is challenging and urgently desirable. Herein, an anion exchange strategy is presented to fabricate Fe‐N4 moieties anchored in hierarchical carbon nanoplates composed of hollow carbon spheres (Fe‐SA/N‐HCS). With the coordinating O atoms are substituted by N atoms, Fe SAs with Fe‐O4 configuration are transformed into the ones with Fe‐N4 configuration during the thermal activation process. Insights into the evolution of central atoms demonstrate that the SAs with specific coordination environment can be obtained by modulating in situ anion exchange process. The strategy produces a large quantity of electrochemical accessible site and high utilization rate of Fe‐N4. Fe‐SA/N‐HCS shows excellent ORR electrocatalytic performance with half‐wave potential of 0.91 V (vs. RHE) in 0.1 M KOH, and outstanding performance when used in rechargeable aqueous and flexible Zn‐air batteries. The evolution pathway for SAs demonstrated in this work offers a novel strategy to design SACs with various coordination environment and enhanced electrocatalytic activity. [ABSTRACT FROM AUTHOR]

A unique example of a bis‐zinc‐porphyrin chemical system in which both macrocycles are covalently connected with a single, short buta‐1,3‐diyne linkage placed at the ortho sites of the meso phenyl rings is presented. This dimeric compound resulted from an homo‐coupling side‐reaction taking place during a copper‐catalyzed click reaction between an alkyne porphyrin and 2‐azidopyridine derivatives. Its unexpected formation was rationalized by control experiments and an improved synthesis was achieved under copper‐catalyzed Glaser‐Hay coupling reaction conditions. This highly sterically congested bis‐zinc‐porphyrin derivative behaved as a supramolecular host for encapsulating ditopic molecular guests such as 1,4‐diazabicyclo[2.2.2]octane (DABCO) with association constant K1.1 in the order of 106 M−1. This value is comparable to current systems that typically feature several connecting linkages between the two zinc‐porphyrin sites resulting in (supra)molecular cages ensuring a high pre‐organization. As such, the requirements to take benefit from supramolecular encapsulation can be reduced to a highly rigid, minimal covalent linkage of four atoms between zinc‐porphyrins as herein described. [ABSTRACT FROM AUTHOR]

Elucidating single‐atom effects on the fundamental properties of nanoparticles is challenging because single‐atom modifications are typically accompanied by appreciable changes to the overall particle's structure. Herein, we report the synthesis of a [Cu58H20PET36(PPh3)4]2+ (Cu58; PET: phenylethanethiolate; PPh3: triphenylphosphine) nanocluster—an atomically precise nanoparticle—that can be transformed into the surface‐defective analog [Cu57H20PET36(PPh3)4]+ (Cu57). Both nanoclusters are virtually identical, with five concentric metal shells, save for one missing surface copper atom in Cu57. Remarkably, the loss of this single surface atom drastically alters the reactivity of the nanocluster. In contrast to Cu58, Cu57 shows promising activity for click chemistry, particularly photoinduced [3+2] azide‐alkyne cycloaddition (AAC), which is attributed to the active catalytic site in Cu57 after the removal of one surface copper atom. Our study not only presents a unique system for uncovering the effect of a single‐surface atom modification on nanoparticle properties but also showcases single‐atom surface modification as a powerful means for designing nanoparticle catalysts. [ABSTRACT FROM AUTHOR]

Elucidating single‐atom effects on the fundamental properties of nanoparticles is challenging because single‐atom modifications are typically accompanied by appreciable changes to the overall particle's structure. Herein, we report the synthesis of a [Cu58H20PET36(PPh3)4]2+ (Cu58; PET: phenylethanethiolate; PPh3: triphenylphosphine) nanocluster—an atomically precise nanoparticle—that can be transformed into the surface‐defective analog [Cu57H20PET36(PPh3)4]+ (Cu57). Both nanoclusters are virtually identical, with five concentric metal shells, save for one missing surface copper atom in Cu57. Remarkably, the loss of this single surface atom drastically alters the reactivity of the nanocluster. In contrast to Cu58, Cu57 shows promising activity for click chemistry, particularly photoinduced [3+2] azide‐alkyne cycloaddition (AAC), which is attributed to the active catalytic site in Cu57 after the removal of one surface copper atom. Our study not only presents a unique system for uncovering the effect of a single‐surface atom modification on nanoparticle properties but also showcases single‐atom surface modification as a powerful means for designing nanoparticle catalysts. [ABSTRACT FROM AUTHOR]

Photoexcitation of trapped ions by Hermite–Gaussian (HG) modes from guided beam structures is proposed and investigated theoretically. In particular, simple analytical expressions for the matrix elements of induced atomic transitions are derived that depend both on the parameters of HG beams and on the geometry of an experiment. By using these general expressions, the 2S1/2→2F7/2$^{2}S_{1/2} \rightarrow \; ^{2}F_{7/2}$ electric octupole (E3) transition is investigated in an Yb+ ion, localized in the low–intensity center of the HG10 and HG01 beams. It is shown how the corresponding Rabi frequency can be enhanced by properly choosing the polarization of incident light and the orientation of an external magnetic field, which defines the quantization axis of a target ion. The calculations, performed for experimentally feasible beam parameters, indicate that the achieved Rabi frequencies can be comparable or even higher than those observed for the conventional Laguerre–Gaussian (LG) modes. Since HG‐like modes can be relatively straightforwardly generated with high purity and stability from integrated photonics, these results suggest that they may form a novel tool for investigating highly‐forbidden atomic transitions. [ABSTRACT FROM AUTHOR]

Open‐[60]fullerenes possessing a huge orifice with a ring‐atom count exceeding 19 have been confined to only a few examples. Herein, we report a 20‐membered‐ring orifice which enables for a guest molecule such as H2, N2, and CH3OH to be encapsulated inside the [60]fullerene cavity. In addition, a 21‐membered‐ring orifice was prepared via a reductive decarbonylation, in which one of the carbon atoms was moved out of the [60]fullerene skeleton as an N,N‐dimethylamide group. At a low temperature of −30 °C, an Ar atom was encapsulated with an occupation level up to 52 %. At around room temperature, the amide group on the orifice rotates along with the C(amide)−C(fullerene) bond axis, realizing a self‐inclusion of the methyl substituent on the amide group as confirmed NMR spectroscopically and computationally. [ABSTRACT FROM AUTHOR]

An atroposelective Ir‐catalyzed dynamic kinetic resolution (DKR) of 2‐(quinolin‐8‐yl)benzaldehydes/1‐naphthaldehydes by transfer hydrogenative coupling of allyl acetate is disclosed. The allylation reaction takes place with simultaneous installation of central and axial chirality, reaching high diastereoselectivities and excellent enantiomeric excesses when ortho‐cyclometalated iridium‐DM‐BINAP is used as the catalyst. The racemization of the substrates occurs through a designed transient Lewis acid‐base interaction between the quinoline nitrogen atom and the aldehyde carbonyl group. [ABSTRACT FROM AUTHOR]

An atroposelective Ir‐catalyzed dynamic kinetic resolution (DKR) of 2‐(quinolin‐8‐yl)benzaldehydes/1‐naphthaldehydes by transfer hydrogenative coupling of allyl acetate is disclosed. The allylation reaction takes place with simultaneous installation of central and axial chirality, reaching high diastereoselectivities and excellent enantiomeric excesses when ortho‐cyclometalated iridium‐DM‐BINAP is used as the catalyst. The racemization of the substrates occurs through a designed transient Lewis acid‐base interaction between the quinoline nitrogen atom and the aldehyde carbonyl group. [ABSTRACT FROM AUTHOR]

The asymmetric hydrophosphination of cyclopropenes with phosphines is of much interest and importance, but has remained hardly explored to date probably because of the lack of suitable catalysts. We report here the diastereo‐ and enantioselective hydrophosphination of 3,3‐disubstituted cyclopropenes with phosphines by a chiral lanthanocene catalyst bearing the C2‐symmetric 5,6‐dioxy‐4,7‐trans‐dialkyl‐substituted tetrahydroindenyl ligands. This protocol offers a selective and efficient route for the synthesis of a new family of chiral phosphinocyclopropane derivatives, featuring 100 % atom efficiency, good diastereo‐ and enantioselectivity, broad substrate scope, and no need for a directing group. [ABSTRACT FROM AUTHOR]