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We report herein an enantioselective acyl transfer protocol via electrophile activation. The reaction cascade sequence encompasses dinuclear zinc-catalyzed asymmetric Michael addition, intramolecular cyclization, and retro-Claisen reaction, which leads to a step- and atom-economic approach to a variety of protected cyclic tertiary α-hydroxyketones in good yields with excellent enantioselectivities (24 examples, 56%-82% yield, 1.5-13 dr and 79%-96% ee). Besides, the large-scale synthesis and further transformation of the products demonstrate the effectiveness of this method for organic synthesis. LESS      Full article

Photothermal cancer therapy has attracted plenty of attention in the last decades due to its promising efficacy, spatiotemporal control, negligible drug resistance, etc. However, to achieve widespread clinical application, studies in the field of photothermal therapy still need to focus on the improvement of efficacy and the minimization of side effects. Host-guest assemblies, constructed by the inclusion of small molecular guests into macrocyclic hosts through non-covalent interactions, are featured with unique microenvironments and flexible, dynamic nature. Based on the abovementioned advantages, host-guest assemblies show great potential in photothermal therapy. However, presumably, the endeavors of host-guest assemblies-based photothermal therapy have not been systematically discussed. Hence, to benefit the design of advanced host-guest assembly-based photothermal agents and promote the development of photothermal therapy, in this review, the major achievements of host-guest assemblies in photothermal cancer therapy, including the enhancement of photothermal conversion efficiency, the improvement of targeted distribution at tumor sites, and the superiority of constructing photothermal therapy-derived multimodal synergistic therapy, are discussed. In addition, the future perspectives on host-guest assemblies-based photothermal therapy are outlined. LESS      Full article

Metal-Nitrogen-Carbon (M-N-C) materials are the most promising Platinum-group-metal (PGM)-free catalysts in replacing the high-cost and scarce Pt catalysts in proton exchange membrane fuel cells (PEMFCs). However, while striking improvement of M-N-C catalysts has been reached in activity, the headache degradation problems hinder their real-world application. Herein, we present a comprehensive overview of the durability of the M-N-C catalyst for oxygen reaction reduction (ORR). The fundamental understanding and identification of the ORR performance of M-N-C catalysts are discussed. Meanwhile, the standard methods to evaluate and predict the ORR performance of the PGM-free catalysts are suggested. We mainly introduce the durability challenges of the M-N-C catalyst and explain the inactivation mechanism in detail. The proposed solution and useful strategies to alleviate catalyst degradation are systematically summarized to overcome the durability bottlenecks. LESS      Full article

Selenium (Se), as an intriguing chalcogenide semiconductor, has traditionally been used for solar energy harvesting. The recent development of nanoscience and nanotechnology has enabled a myriad of Se nanomaterials with compelling structures and unique features. Compared with other chalcogens, Se nanomaterials possess anisotropic crystalline structure, intrinsic chirality, and high reactivity, as well as unique optical, electrical, photoconductive, and piezoelectrical properties. The integration of these Se nanomaterials with technologically important materials, such as conductors and semiconductors, over flexible, bendable, stretchable, and highly curved substrates offer a new generation of Se nanomaterial-based flexible and wearable electronics. In this mini review, we survey the recent scientific and technological breakthroughs in Se nanomaterials-enabled flexible and wearable electronics. We highlight the synthesis, fabrication, morphologies, structure, and properties (optical, electrical, optoelectrical, photovoltaic, and piezoelectric) of Se nanomaterials as well as their integration into innovative functional devices that deliver higher forms of applications across smart sensing, health care, and energy domains. We conclude with a critical analysis of existing challenges and opportunities that will trigger the continued progress of the field. LESS      Full article

A series of alkynylplatinum(II) terpyridine complexes and alkynylplatinum(II) terpyridine-containing conjugated polymers with different polymer backbones has been synthesized, and their spectroscopic properties and Förster resonance energy transfer (FRET) processes has been investigated. The platinum(II)-containing polymers exhibit dual emissive features with emission maxima at ca. 416-465 nm and ca. 671-673 nm, which are assigned to be originated from singlet intraligand (¹IL) excited states from the polymer backbone and triplet metal-metal-to-ligand charge transfer (³MMLCT) excited states from the platinum(II) pendants, respectively. The Förster radii (R₀) of the platinum(II)-containing conjugated polymers have been determined, and their distinctive thermo-responsive luminescence changes have also been observed. The present work has demonstrated the utilization of “click” reaction for the preparation of platinum(II)-containing conjugated polymers, which show unique photophysical and spectroscopic properties. Through the judicious design, this type of platinum(II)-containing polymer is found to be sensitive to temperature, resulting in ratiometric emission changes. This study has provided valuable insights into the preparation of metal-containing polymeric systems for different applications. LESS      Full article

Sulfur-based ylides are very important and valuable reagents in organic synthesis and have been widely applied in the preparation of cyclic compounds and the formation of C-X (X = C, N, O, S, B, P) bond. Since the early 2000s, asymmetric organocatalysis has become a powerful strategy in organic synthesis (even highlighted by the 2021 Nobel Prize in Chemistry) and has attracted widespread research interest among synthetic organic chemists. In this area, a large number of outstanding achievements have been registered in the novel chiral catalysts design, new compounds synthesis, various reagents application, and versatile reaction discovery. Given the extensive application of sulfonium and sulfoxonium ylides in organic synthesis, in this review, we mainly summarize the organocatalyzed asymmetric reactions involving these ylide reagents as one of the reactants. Detailed reaction mechanisms, transition states and some synthetic applications are highlighted. The challenges and opportunities of this field are also discussed in the outlook. LESS      Full article

The direct enantioselective construction of axially chiral 3-arylindole frameworks via nucleophilic addition of 2-substituted indoles to iminoquinones has been achieved with high efficiencies under mild chiral phosphoric acid (CPA) catalytic conditions. The utility of this method was demonstrated in successful scale-up syntheses without compromising the product yields and enantioselectivities. The oxidation of products yields axially chiral heteroaryl-p-quinone monoimine, which could be subjected to structural diversification via addition of nucleophiles. LESS      Full article

Water shortage is an increasing threat to humankind. Porous sorbent assisted atmospheric water harvesting (psaAWH) has emerged as an effective technological countermeasure. In this review, we summarize the types of porous adsorbents used in psaAWH and provide an overview of their states of development. The water adsorption mechanism and the processes associated with each material are analyzed, and the application prospects of the adsorbents are evaluated. The effect of the inherent properties (pore size, functional group, etc.) of the adsorbent on the water harvesting performance is also discussed. Further, we focus on the water adsorption/desorption kinetics of the adsorbents and outline various methods to improve the kinetics. At this stage, there are many strategies for improving the kinetics of the adsorbent, which in turn influences the adsorption process and intra/inter-crystalline diffusion. However, there is still limited research on the transport of water molecules in microporous adsorbents for psaAWH. Thus, this aspect is re-examined herein from a new perspective (superfluidity) in the review. Based on the discussion, we can reasonably infer that water molecule superfluidity can exist in nanoconfined channels, thus promoting the rapid transport of water molecules. The formation of water superfluidity is a feasible strategy for improving the intracrystalline diffusion of the psaAWH adsorbent. Finally, we consider the future developments and challenges of psaAWH in detail. We think this review can serve as a guide for further research in this ever-expanding field. LESS      Full article

Quinidine-catalyzed regio- and enantioselective formal [4 + 2]-cycloadditions of 2-(4H-benzo[d][1,3]oxazin-4-yl)acrylates with N-tosyl-2-methylenebut-3-enoates and 2-methylene-3-oxoalkanoates have been developed for the first time. The reaction features the in situ formation of chiral nitrogen-containing dipolar intermediates, a ring-opening/Michael addition/annulation cascade reaction, and works well over a broad substrate scope to furnish the tetrahydroquinolines in high yields with high asymmetric induction under mild conditions. LESS      Full article

Modulating the electrocatalytic performance of Palladium (Pd) with nonmetallic elements (e.g., H, B, C, N, O, P and S) has gained ever-increasing attention since their introduction has been proven to effectively modulate the 3d-electronic configuration and subsurface properties of Pd. In this review, the most advanced nonmetal-modified Pd-based catalysts are classified according to the different doped atoms (i.e., hydrides, borides, carbides, nitrides, oxides, phosphides and sulfides) and critically reviewed to emphasize the roles of nonmetallic elements doping on various electrocatalytic reactions. In each section, the synthetic strategies developed to incorporate nonmetals are discussed in detail. Furthermore, the optimized approaches of nonmetals-doped Pd-based catalysts and corresponding electrocatalytic enhancement mechanisms are also discussed clearly. Finally, the current challenges and future perspectives regarding nonmetal-modified Pd-based nanocatalysts are also outlined. LESS      Full article