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In recent years, mechanochemistry has become recognized as an efficient, practical, and sustainable alternative for chemical synthesis. Adhering to the principles of green chemistry, mechanochemistry enables solvent-free, faster, and energy-efficient reactions, thereby reducing waste production and enhancing atom economy. Herein, we present a new nickel-catalyzed mechanochemical High Throughput Experimentation (HTE) amination protocol enabled by Resonant Acoustic Mixing (RAM). The developed C–N cross-coupling reactions avoid possible contamination, scaling-up challenges, and parallel reaction limitations by applying an accelerated screening and optimization protocol. The reduced amount of solvents in the reactions and the minimal amount of reagents required highlight the advantages of our approach over most common solvent-based reactions, aligning with the principles of sustainability and resource efficiency. Furthermore, the mechanochemistry methodology demonstrates seamless scalability to a multigram scale without additional optimizations, emphasizing its potential for streamlined, environmentally friendly, and large-scale industrial production. [ABSTRACT FROM AUTHOR]

We have developed a novel Ni-catalyzed reductive cross-coupling reaction of aryl bromides and alkyl iodides via a photoactive electron donor–acceptor (EDA) complex. This photo-induced process enables the efficient construction of C(sp2)–C(sp3) bonds in the absence of an external photocatalyst. Electronically and structurally diverse aryl bromides, as well as secondary and primary alkyl iodides could undergo this transformation smoothly. Natural product derivatives were employed successfully, and UV-vis spectroscopy was utilized to gain mechanistic insight. [ABSTRACT FROM AUTHOR]

An efficient method for the radical difunctionalization of aromatic alkynes has been developed, resulting in the synthesis of a range of valuable triarylethenes. This approach utilizes strategically designed aryldiazonium salts with tertiary alcohol substitution as bifunctional reagents, along with cost-effective cuprous chloride as a catalyst. The method demonstrates remarkable Z-selectivity and is capable of gram-scale preparation. Additionally, a novel spin-trapping reagent has been developed based on the synthesized product. [ABSTRACT FROM AUTHOR]

This paper investigates physically crosslinked organo-hydrogels for total hip replacement surgery. Current materials in artificial joints have limitations in mechanical performance and biocompatibility. To overcome these issues, a new approach based on hydrogen bonds between polyvinyl alcohol, poly(2-hydroxyethyl methacrylate), and glycerin is proposed to develop bioactive organo-hydrogels with improved mechanical properties and biocompatibility. This study analyzes local pathological characteristics, systemic toxicity, and mechanical properties of the gels. The results show that the gels possess excellent biocompatibility and mechanical strength, suggesting their potential as an alternative material for total hip replacement surgery. These findings contribute to improving patient outcomes in joint replacement procedures. [ABSTRACT FROM AUTHOR]

The identification of cysteine enantiomers is of great significance in the biopharmaceutical industry and medical diagnostics. Herein, we develop an electrochemical sensor to discriminate cysteine (Cys) enantiomers based on the integration of a copper metal–organic framework (Cu-MOF) with an ionic liquid. Because the combine energy of D -cysteine (D -Cys) with Cu-MOF (−9.905 eV) is lower than that of L -cysteine (L -Cys) with Cu-MOF (−9.694 eV), the decrease in the peak current of the Cu-MOF/GCE induced by D -Cys is slightly higher than that induced by L -Cys in the absence of an ionic liquid. In contrast, the combine energy of L -Cys with an ionic liquid (−1.084 eV) is lower than that of D -Cys with an ionic liquid (−1.052 eV), and the ionic liquid is easier to cross-link with L -Cys than with D -Cys. When an ionic liquid is present, the decrease in the peak current of the Cu-MOF/GCE induced by D -Cys is much higher than that induced by L -Cys. Consequently, this electrochemical sensor can efficiently discriminate D -Cys from L -Cys, and it can sensitively detect D -Cys with a detection limit of 0.38 nM. Moreover, this electrochemical sensor exhibits good selectivity, and it can accurately measure the spiked D -Cys in human serum with a recovery ratio of 100.2–102.6%, with wide applications in biomedical research and drug discovery. [ABSTRACT FROM AUTHOR]

Photocatalytic mineralization of organic pollutions and simultaneously converting CO2 to CO (tetracycline → CO2 → CO) represents a fascinating way to solve the environmental and energy crisis. This work demonstrates the excellent mineralization and CO2 reduction performance of S-vacancy CdS and reveals the high efficiency of the carbon self-recycling two-in-one photocatalytic system. [ABSTRACT FROM AUTHOR]

Alkenes, in particular, low-boiling-point alkenes such as ethylene, are bulk chemical materials in the petrochemical industry. Conversion of these inexpensive materials to value-added fine chemicals is of utmost importance. Herein, we report an efficient approach for radical alkylfunctionalization of gaseous ethylene and other light alkenes by remote functional group migration. Various alkyls including deuterated alkyl groups are readily incorporated into alkenes along with the installation of extra heteroaryl or oximino groups, leading to complex functionalized alkanes. This photochemical method is operationally simple, proceeding even in the absence of photosensitizers and transition-metal additives. [ABSTRACT FROM AUTHOR]

Herein, we disclose a novel self-catalytic photochemical sulfonylation of phenothiazines, in which phenothiazine functions as both a substrate and a photosensitizer. The reaction proceeds under visible-light irradiation without an extra photocatalyst and additives and presents a green synthetic approach to access valuable mono- and di-sulfonylated phenothiazines. This late-stage modification process massively enriches the library of phenothiazine-based organophotocatalysts and features operational simplicity, broad functional group compatibility, and high product diversity. [ABSTRACT FROM AUTHOR]

Disclosed herein is the first example of radical-mediated remote migration of quinoxalinones. The quinoxalinonyl-functionalization of alkenes employs the quinoxalinone-substituted tertiary bishomoallylic alcohols as substrates, proceeds through intramolecular 1,4-quinoxalinone migration, and gives rise to complex γ-quinoxalinone-substituted aliphatic ketones. A set of external radicals is compatible with this method. The protocol features broad tolerance of functional groups, good adaptability to various external radicals and high product diversity, and opens a new door for the synthesis of quinoxalinone derivatives. [ABSTRACT FROM AUTHOR]

The popular design of an electronic structure and architecture with appropriate binding strength with oxygen-involved intermediates and abundant active sites is of paramount significance for boosting the oxygen evolution reaction (OER), yet it is still challenging. Herein, an innovative hammer-shaped structure has been well developed by in situ assembly of ZIF-67 nanocubes on the surface of one-dimensional (1D) NiMoO4 nanorods. After doping with an ultralow amount of Ir, the NiMoO4-ZIF hammers are demonstrated to be highly active toward the OER, delivering a current density of 10 mA cm−2 with an ultralow overpotential of 235 mV. On the basis of X-ray photoelectron spectroscopy and surface valence band spectra, it is revealed that the ultralow Ir doping can effectively modify the electronic structure of the metal center, leading to optimization of the binding strength with O* and OOH*. Moreover, the hammer-like architecture and intimate interface between NiMoO4 and in situ formed CoOOH also contribute to the substantial improvement in OER performance. This work manifests the significance of an electronic and architecture engineering strategy for an improvement in electrocatalytic performance and presents an advanced OER electrocatalyst. [ABSTRACT FROM AUTHOR]

Practical, metal-free heteroarylations of C–H and C–C bonds of unprotected aliphatic alcohols are accomplished in a 'stop-flow' micro-tubing reactor. The reactions proceed through alkoxy radical-triggered hydrogen atom transfer and β-C(sp3)–C(sp3) bond rupture under mild photochemical conditions, leading to a plethora of valuable functionalized heteroarenes. The reaction is amenable for late-stage functionalization of complex heteroarenes, and can be readily scaled up by a continuous-flow method. The protocol features many advantages including good regioselectivity, broad functional group compatibility, and easy operation, and may find potential use in medicinal chemistry. [ABSTRACT FROM AUTHOR]

A novel radical-mediated trifunctionalization of hexenenitriles via the strategy of remote functional group migration is disclosed. A portfolio of functionalized hexenenitriles are employed as substrates. After difunctionalization of the unactivated alkenyl part via remote cyano migration, the in situ formed radical intermediate is captured by an azido radical, thus enabling the trifunctionalization. The reaction features mild conditions and broad functional group compatibility, leading to valuable products bearing multiple useful groups. This protocol further extends the scope of remote functional group migration. [ABSTRACT FROM AUTHOR]

Metallaphoto-catalysis has been established as a robust platform for efficient construction of a range of chemical bonds. Moreover, transformation of native functionalities such as C(sp3)–H bonds to produce functional molecules represents one of the most attractive strategies in organic synthesis. Merging two powerful methodologies, metallaphoto-catalyzed benzylic and allylic C(sp3)–H bond functionalizations provide a series of general and mild approaches for diversification of alkylbenzenes and alkenes. [ABSTRACT FROM AUTHOR]

Metal-free C–Se cross-couplings via the formation of electron-donor–acceptor (EDA) complexes have been developed. The visible-light induced reactions can be applied for the synthesis of a series of unsymmetrical diaryl selenides employing aryl bromides, aryl iodides as well as aryl chlorides under mild reaction conditions. The scale-up was readily achieved. UV-Vis spectroscopy measurements provide insight into the reaction mechanism. [ABSTRACT FROM AUTHOR]

As a thermoelectric material, p-type CuSbSe2 has attracted much attention due to its intrinsic low thermal conductivity and environment friendly constituents. In this work, Sb deficient compounds CuSb1−xSe2 (x = 0–0.12) are prepared by vacuum melting with spark plasma sintering (SPS) and their thermoelectric properties are studied. It is found that when CuSb1−xSe2 samples are deficient in Sb (i.e., x > 0), their electrical conductivity increases by more than two times (at 300 K) due to the increase in hole concentration caused by Sb vacancies,. Moreover, experiments show that as the Sb vacancy concentration x increases to 0.09, the density of states effective mass is enhanced by ∼3 times, which leads to the 70% enhancement of thermopower (at 300 K). In addition, around 22% reduction of lattice thermal conductivity is observed due to the intensified phonon scattering by Sb vacancies, phonon–phonon scattering and phase boundaries. As a result, a peak power factor of 3.2 μW cm−1 K−2 and a maximum figure of merit ZT of 0.50 are achieved at 673 K for CuSb0.91Se2, which are ∼38% and ∼44% larger than those of pristine CuSbSe2. [ABSTRACT FROM AUTHOR]

Rearrangement reactions, one of the most significant transformations in organic chemistry, play an irreplaceable role in improving synthetic efficiency and molecular complexity. Concomitant cleavage and reconstruction of chemical bonds can display the great artistry and the glamour of synthetic chemistry. Over the past century, ionic rearrangement reactions, in particular those involving cationic pathways, have represented most of the research. Alongside the renaissance of radical chemistry, radical-mediated rearrangements have recently seen a rapid increase of attention from the chemical community. Many new radical rearrangements that extensively reveal the migratory behaviour of functional groups have been unveiled in the last decade. This Review provides a comprehensive perspective on the area from the past to present achievements, and brings up the prospects that may inspire colleagues to develop more useful synthetic tools based on radical rearrangements. [ABSTRACT FROM AUTHOR]

Disclosed herein is a novel radical-mediated intermolecular carboarylation of alkenes by cleaving inert C–O bonds. The strategically designed arylbenzothiazolylether diazonium salts are harnessed as dual-function reagents. A vast array of alkenes are proven to be suitable substrates. The benzothiazolyl moiety in the products serves as the formyl precursor, and the OH residue provides the cross-coupling site for further product elaboration, indicating the robust transformability of the products. [ABSTRACT FROM AUTHOR]

Alloying is one of the most effective strategies to change the properties of inorganic–organic hybrid materials, but there are few reports of the alloying of one-dimensional nanowires with precise atomic structure due to the difficulties in obtaining the single crystals of nanowires themselves. Herein, we describe the synthesis and characterization of an alloyed one-dimensional Ag–Cu nanowire [Ag2.5Cu1.5(S-Adm)4]n. Compared with the unalloyed [Ag4(S-Adm)4]n, our novel alloyed nanowire exhibits good conductivity, and its resistivity (as a powder) was determined to be 107 Ω m by impedance analysis–consistent with that of a semiconductor. Accordingly, based on these properties combined with its excellent thermal stability and high-yielding, gram-scale synthesis, [Ag2.5Cu1.5(S-Adm)4]n is proposed for electronic-device applications. [ABSTRACT FROM AUTHOR]

Bicyclo[1.1.1]pentane (BCP) is widely applied as the bioisostere for aryl, internal alkynes, and tert-butyl groups in medicinal chemistry. We herein disclose an efficient and practical preparation of sulfonyl alkynyl/allyl/cyano-substituted BCP derivatives through a novel radical-mediated difunctionalization of propellane. The radical alkynylation, allylation, and cyanation processes readily proceed under mild photochemical conditions. The synthetic method features broad functional group tolerance, high product diversity, gram-scale preparation, and excellent atom-economy. [ABSTRACT FROM AUTHOR]

Nanoparticles are often used to serve as drug delivery systems to improve the therapeutic efficacy of some hydrophobic drugs. In this work, PEG and peptide-modified titanium phosphate nanoparticles (TiP–PEG/peptide) were synthesized to enhance the drug delivery efficacy of tirucalla-8,24-diene-3β,11β-diol-7-one (KS-01), a major bioactive and hydrophobic component extracted from Euphorbia kansui. This drug delivery system with a loading efficiency of about 29.8 mg KS-01/1 g TiP–PEG/peptide exerted a significantly lower cell viability rate of MCF-7 than free KS-01, indicating that these carriers can effectively increase the therapeutic efficacy by improving its water solubility. Moreover, according to the fluorescence intensity of FAM which can be generated by caspase-3 cleaving DEVD-embedded peptide, the caspase-3 level could be determined and the therapeutic efficacy could be visualized in real time. [ABSTRACT FROM AUTHOR]

Aqueous electrochemical conversion of CO2 with renewable energy is a sustainable pathway to produce carbon-neutral fuels and address the growing crisis of global warming. A key challenge in the field of electrochemical CO2 reduction (CO2R) is the design of catalytic materials featuring high product selectivity, stability, and a composition of earth-abundant elements. In this work, we demonstrate anion exchange as a promising strategy to achieve synergistic catalysis via secondary coordination sphere interactions between the catalyst and the support. We encapsulate an anionic cobalt porphyrin-based electrocatalyst, with a single-molecule dispersion, into a cationic porous polymer skeleton, and construct a class of electrocatalysts to convert CO2 to CO with remarkable activity, selectivity and durability. Detailed examination of CO2R revealed selectivity for CO production in excess of 83% and stability over 7 hours with a per-site turnover frequency of 1.4 s−1. In situ spectroelectrochemical measurements using surface-enhanced infrared absorption spectroscopy (SEIRAS) provided insights into the capability of the cationic polymer framework to control the interactions of intermediates with groups in close proximity via modifying the secondary coordination sphere interactions around the active sites. Our findings highlight the importance of a rationally designed electrocatalyst/solid support interface and offer a paradigm to integrate catalytically active components and develop efficient electrocatalytic systems via marrying the catalyst and support, and creating synergy. [ABSTRACT FROM AUTHOR]

CuGaTe2 based chalcopyrite materials have attracted intense research interest due to their high power factor. However, it is difficult to substantially improve the thermoelectric performance because of their high thermal conductivity. Here we simultaneously optimize their thermoelectric and mechanical properties by introducing carbon particles (CPs) into the CuGaTe2 matrix. Firstly, as electron localization centers, the introduced carbon particles can enhance their electrical conductivity and thereby the power factor by adjusting the electrical transport properties. Secondly, the interfaces between carbon particles and the matrix can strongly scatter the heat carrying phonons and suppress their thermal conductivity, leading to ∼41% decrease in lattice thermal conductivity at 873 K. The highest ZT value (∼1.0@873 K) is obtained for CuGaTe2 + 0.5 wt.% CPs, which is ∼28% larger than that of pure CuGaTe2. Thirdly, the softer carbon particles can simultaneously optimize the hardness and fracture toughness of the composites, which is beneficial for the techniques used in the processing of thermoelectric devices. The hardness is decreased from 4.45 to 3.82 GPa and the fracture toughness is increased from 0.80 to 1.10 MPa m1/2 after introducing 0.5 wt.% CPs into the CuGaTe2 matrix, respectively. All results indicate that the incorporation of carbon particles is a very promising approach for improving the thermoelectric and mechanical properties of CuGaTe2. [ABSTRACT FROM AUTHOR]

Direct functionalization of inert C(sp3)–C(sp3) and C(sp3)–H bonds represents one of the most valuable synthetic tactics, yet large obstacles remain in terms of reactivity and selectivity. Alkoxy radicals enable C–C bond scission via β-C elimination and C(sp3)–H bond cleavage through a hydrogen atom transfer (HAT) process, thus providing an efficient method to address these problems. In view of atom- and step-economy, the direct use of abundant alcohols as alkoxy radical precursors in radical transformations is of high synthetic value. This feature article summarizes our recent achievements in (a) C(sp3)–C(sp3) bond cleavage via ring-opening of cycloalkanols and (b) site-specific C(sp3)–H functionalization of unprotected aliphatic alcohols, along with the reconstruction of various new chemical bonds, e.g. C–halogen, C–C, C–N, C–S, and C–Se bonds. [ABSTRACT FROM AUTHOR]

Disclosed herein is a novel, metal-free synthesis of γ-lactams through the radical-mediated nitration–aminocarbonylation of unactivated olefins. The reaction is initiated by a nitro radical generated from the homolysis of tert-butyl nitrite. The intramolecular cyanamide serves as the aminocarbonylating reagent. This protocol offers an environment-benign method to produce the synthetically valuable nitromethyl substituted γ-lactams. [ABSTRACT FROM AUTHOR]