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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]

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(sp 2 )-C(sp 3 ) 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.

Pyrroline derivatives are common in bioactive natural products and therapeutic agents. We report here a synthesis of pyrrolines and fused diaziridines by divergent radical cyclization of homoallylic diazirines, which can serve as an internal radical trap and a nitrogen source. This reaction proceeds by selective radical addition to C[double bond, length as m-dash]C or N[double bond, length as m-dash]N bonds followed by intramolecular cyclization. Frontier molecular orbital analysis provides a deep insight into the origin of the selectivity. The reaction demonstrates a new cyclization mode, broad functional group compatibility and high product diversity, and reveals a much broader chemical space for diazirine studies., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Upgrading methane into methanol or other high value-added chemicals is not only beneficial to mitigate the greenhouse effect, but also provides basic raw materials for industrial production. Nowadays, most research is limited to zeolite systems, and it is a considerable challenge to extend the support to metal oxides while achieving a high yield of methanol. In this paper, we take advantage of impregnation methods to synthesise a novel Cu/MoO 3 catalyst, which can convert methane to methanol in the gaseous phase. At 600 °C, the Cu(2)/MoO 3 catalyst can achieve a maximum STY CH 3 OH of 47.2 μmol (g -1 h -1 ) with a molar ratio CH 4  : O 2  : H 2 O = 5 : 1.4 : 10. Consequences of SEM, TEM, HRTEM and XRD substantiate that Cu is incorporated into the lattice of MoO 3 to form CuMoO 4 . And transmission infrared spectroscopy, Raman spectroscopy together with XPS characterization techniques confirm the generation of CuMoO 4 , which is the main active site provider. This work provides a new support platform for Cu-based catalyst research in the methane-to-methanol system., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

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(sp 3 )-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(sp 3 )-H bond functionalizations provide a series of general and mild approaches for diversification of alkylbenzenes and alkenes.

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.