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We report the construction of C5‐indole unnatural amino acid derivatives via the diastereoselective Pd(II)‐catalyzed prochiral β‐C(sp3)‐H arylation of racemic (DL), and enantiopure L‐ and D‐carboxamides of amino acids with 5‐iodoindoles. Independently, indole‐based compounds and amino acid motifs are important small molecules in organic synthesis and drug discovery research. This report aimed to contribute to enriching the library of indole‐based unnatural amino acid derivatives. The synthesis of examples of C5‐indole motif‐installed amino acid derivatives comprising norvaline, phenylalanine, leucine, norleucine, 2‐aminooctanoic acid having anti‐stereochemistry was accomplished. The synthesis of the C5‐indole motif‐containing non‐α‐amino acid (aminoalkanoic acid) derivatives was also reported. The C−H arylation reactions of racemic and enantiopure carboxamides with 5‐iodoindoles afforded the corresponding indole unnatural amino acid derivatives with good diastereoselectivity (anti, dr>95 : 5 and enantiopurity (er up to 99 : 1). Removal of the directing group (8‐aminoquinoline), phthalimide group and preparation of indole amino acid esters and free amino group‐containing indole unnatural amino acid motifs were also shown. The utility of the methodology was shown by synthesizing indole motif‐containing pyrrolidone and peptide molecules. The stereochemistry of the major (anti) diastereomers was ascertained from the X‐ray structure of a representative compound. [ABSTRACT FROM AUTHOR]

Transition metal-based perovskites have emerged as highly promising and economically advantageous semiconductor materials due to their exceptional performance in optoelectronics, photovoltaic, photocatalysis, and photoluminescence. In this study, we employed a microwave-assisted hydrothermal process to produce a Cu-doped NiMnO3 nanocomposite electrode material. The appearance of a peak corresponding to the (110) plane with a 2θ value of 36.6° confirmed the growth of the rhombohedral NiMnO3 crystal structure. The presence of metal–oxygen bonds in NiMnO3 was confirmed through FTIR spectra. XPS validates the chemical composition, providing additional support for the results obtained from XRD and FT-IR analyses. FE-SEM affirmed the anisotropic growth of small sphere-like structures that agglomerated to form broccoli-like shapes. Cu doping modified the band gap, reducing it from 2.2 to 1.7 eV and enhancing its photoluminescent (PL) activity by introducing defects. The increase in PL intensity (visible light luminescent intensity) can be attributed to a concurrent rise in complex defects and the rate of recombination of electron–hole pairs. Finally, the electrochemical activity demonstrated the pseudo-capacitor behavior of the synthesized material, with capacitance values increasing as the copper (Cu) content in the parent lattice increased. [ABSTRACT FROM AUTHOR]

In the present article we report a comparative experimental and theoretical study on the structural and optical properties of ZnO. First principle calculations were carried out using density functional theory (DFT) to study the electronic structure of ZnO. The direct‐type band gap was found in the ZnO's typical estimated energy band structure in the Brillouin zone path G‐G or in the middle of the Γ k‐point grid. To develop UV/ZnO/O2/H2O2 system for photodegradation of organic contaminants in an aqueous system, zinc oxide (ZnO) nanostructures were synthesized using an ultrasonication process at ambient temperature. To test the photocatalytic activity of synthesized nanostructures, we used phenol red (PR) dye as a test substrate. We found that ZnO nanostructures photo‐degraded PR dye at a rate of over 90% under ultraviolet light irradiation, converting photonic energy into chemical energy (photocatalytic energy conversion) that can be used for water purification. To explore the structural, optical, morphological, and compositional characteristics of synthesized ZnO nanostructures, various techniques including powder X‐ray diffraction, Fourier‐transform infrared spectroscopy, UV‐visible spectroscopy, scanning electron microscopy, and energy dispersive X‐ray spectroscopy were used. [ABSTRACT FROM AUTHOR]

In this paper, the hydrothermal synthesis of TiO2 nanostructures was analyzed for their structural, morphological, elemental, and optical Properties. X‐ray diffraction (XRD) confirms a highly crystalline nature and reveals that the TiO2 nanocrystals crystallize in the body‐centered tetragonal phase. Scanning electron microscopy (SEM) results show that all the samples are composed of microspheres that are formed from the agglomeration of smaller nanoparticles. The size of the microspheres varies from sample to sample and has a direct relation to the volume of the precursors used. Energy‐dispersive X‐ray analysis (EDAX) shows that the synthesized materials are in good stoichiometry with uniform distribution of the constituents throughout the sample. Fourier transform infrared spectrum of different samples showed a 100% transmittance peak in the 500 to 1000 cm−1 region. Ultraviolet (UV) and visible spectroscopy shows that the material has a good absorption in the visible region and is suitable for photocatalysis. The bandgap of the samples was determined by using the Tauc plot. The synthesized material was used for the photocatalytic degradation of methyl red (MR), a hazardous dye. The 95% degradation of MR occurred in the presence of UV light. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of MnTiO3 nanoparticles employing a simple, eco‐friendly and low‐cost hydrothermal method. The properties of MnTiO3 nanoparticles were analysed by XRD, FTIR, FE‐SEM, TEM and thermogravimetric analysis (TGA). Structural properties revealed that the MnTiO3 have rhombohedral phase. Morphological studies revealed that the synthesised sample has granular‐like structure. FTIR technique confirmed the formation of MnTiO3 nanoparticles. TGA shows that the as synthesised sample is thermally more stable. The electrochemical detection of acetaminophen (AMP) by using nano‐perovskite‐type manganese titanate (MnTiO3)‐modified glassy carbon electrode is reported. The conductive behaviour of MnTiO3‐modified glassy carbon electrode (MnTiO3/GCE) was confirmed by cyclic voltammetry (CV). Differential pulse voltammetry (DPV) was employed for the detection of AMP. DPV technique showed a comparatively lower detection potential with a higher peak response towards AMP sensing with a linear range of 1.3 to 13.8 μM. The limit of detection and sensitivity were found 1.26 μM and 36.22 μA μM−1 m−2, respectively. Moreover, the modified electrode also demonstrated better repeatability, reproducibility and higher stability, hence used for the analysis of AMP in pharmaceutical and human serum samples with good recoveries. Electrochemical properties showed that the MnTiO3 perovskite has specific capacitance 357.2 F g−1 revealing its charge storing ability. [ABSTRACT FROM AUTHOR]

The present article reports the synthesis, characterization and spin-polarized electronic structure of Cu2MnSnS4 (CMTS) quantum dots. Optimization of the hydrothermal physical parameters including reaction temperature and duration has been performed. The CMTS material synthesized was characterized for its structural, morphological, chemical, compositional optical and electrochemical properties. Variation of the reaction parameters made it possible to get an idea about the process of material formation. Formation mechanism, secondary phase detection and single-phase crystallinity are achieved robustly. Single phase tetragonal CMTS was synthesized just after 8 h reaction duration. Significant reactions parameters like, prolonged reaction duration and higher temperatures influence the morphology and hence resulted in enhanced crystallinity of these nanostructures. Variable structural morphologies and shapes like polygons, cauliflower and quantum dots as small as 4–5 nm were synthesized. Optical properties indicated that the quantum dots are highly active in the visible range of the optical spectrum. Also, the electronic structure calculations for this material tracked the 1.4 eV band gap confirmed from absorption spectrum. Electrochemical properties showed the material is having pseudocapacitive nature exhibiting specific capacitance of 268 F/g revealing its charge storing ability. [ABSTRACT FROM AUTHOR]

Azobenzene-based unnatural amino acid motifs were synthesized via Pd(II)-catalyzed diastereoselective C(sp3)–H arylation of amino acid carboxamides with iodoacetanilides and Mills azo coupling. [ABSTRACT FROM AUTHOR]

We have shown our efforts toward expanding the utility of the relatively inexpensive pyridine‐N‐oxide directing group in the Pd(II)‐catalyzed site‐selective γ‐C(sp2)−H, γ‐C(sp3)−H and δ‐C(sp2)−H functionalization. The functionalization β−C−H bonds using bidentate directing group (DG) pyridine‐N‐oxide which operates through the N,O‐coordination mode has been well documented in the literature. However, there exist rare reports dealing with the functionalization of remote sp2/sp3γ‐ and δ‐C−H bonds of carboxamides assisted by the bidentate directing groups operating via the N,O‐coordination. In this paper, the scope of pyridine‐N‐oxide DG was examined for accomplishing the site‐selective (mono) γ‐C(sp2)−H arylation in substrates containing competitive C(sp3)−H and C(sp2)−H bonds. The investigation has enabled to assemble a library of pyridine‐N‐oxide‐based biarylacetamides, heteroaryl‐based biaryl carboxamides, tricyclic quinolones, arylheteroarylmethanes, biaryl‐based aliphatic carboxamides and mono (ortho) arylated phenylglycine derivatives. In general, biaryl derivatives and in particular, arylacetamide, arylacetic acid derivatives and pyridine‐N‐oxide (2‐aminopyridyl) motifs are medicinally relevant classes of compounds. This work enabled the assembling of a library of the above‐mentioned types of compounds through the pyridine‐N‐oxide directing group‐aided site‐selective sp2/sp3γ‐C−H and sp2δ‐C−H functionalization of carboxamides. [ABSTRACT FROM AUTHOR]

In this study, we report the fabrication of binary chalcogenide zinc sulfide (ZnS) quantum dots (QDs) paying a facial, economical, eco‐friendly, and template‐free chemical method. The as‐synthesized nanomaterial has a single cubic phase; based on its structural features, it was confirmed that the nanoparticles are grown as QDs (2‐10 nm). Morphological studies display the formation of agglomerated QDs (3 nm). The energy‐dispersive spectroscopy shows that the essential elements are in the stoichiometric ratio as in the precursor solutions. Optical properties confirmed that the QDs are suitable for optoelectronic devices revealing room‐temperature photoluminescence. The charge‐storage electrochemical activity was explored via electrochemical characterization performances. Electrochemical studies show that the synthesized material has charge storage ability. And according to the International Commission on Illumination, the ZnS QDs show green emission, thus presenting that the material will be useful for biological applications. In addition, these nanoparticles exhibit incredible anticancer activities especially against breast cancer cells and may be used for biological or biomedical applications as well. [ABSTRACT FROM AUTHOR]

Present paper highlights the adsorption performances of mordenite (MOR), polyaniline-mordenite (PANI/MOR), copper oxide-mordenite (CuO/MOR) and silver oxide-mordenite (AgO/MOR) nanocomposites toward decontamination of toxic chemical warfare agent's (CWA)simulant 2-chloroethyl ethyl sulfide (CEES, blistering agent simulant) and dimethyl methyl phosphonate (DMMP, nerve agent simulant) at normal condition of temperature (30 ± 2 °C) and pressure. Composite of MOR zeolite with polyaniline (PANI) was prepared by oxidative polymerization using ammonium per sulfate as an initiator. The composites of MOR zeolite and metal oxide (CuO/MOR) and (AgO/MOR) were prepared by taking aqueous solution of corresponding metal nitrates using ion exchange technique. Adsorption experiments were monitored by gas chromatography – flame ionize detector (GC-FID) to detect ions concentration. Nanocomposites were characterized by techniques such as XRD, FTIR, FESEM-EDX, TGA, UV-Vis and BET. X-ray diffraction (XRD) pattern shows the crystalline nature of parent zeolite and its nanocomposites. Field emission scanning electron microscopy (FESEM) analysis reveals that mordenite, PANI/MOR and AgO/MOR have polyhedron, agglomerated rough and fibrous elongated surfaces, respectively. From SEM analysis, obtained particle size was in the range of 2 to 14.5 μm. Brunauer–Emmett–Teller (BET) analysis depicts that the surface area of MOR, PANI/MOR, AgO/MOR and CuO/MOR were 93.07, 166.49, 120.31and 93.51 m2/g, respectively. AgO/MOR and PANI/MOR nanocomposites were found good adsorbent candidate. The nanocomposite of AgO/MOR was able to decontaminate ∼ 100% in 6 h. We are also able to remove DMMP by PANI/MOR up to ∼ 100%. [ABSTRACT FROM AUTHOR]

In this study, novel growth of WO3-ZnSe nanocomposites was carried out by a simple, low-cost hydrothermal process under subcritical conditions and is reported for the first time in just 5 h. The products were characterized in detail by multiform techniques: X-ray diffraction, scanning electron microscopy (SEM), optical studies, and Fourier transform analysis. The influence of ZnSe on the structural, morphological, compositional, optical, and catalytic properties of WO3 is demonstrated. The WO3 metal oxide material is grown in a hexagonal crystal structure with wide-band-gap and has been modified by ZnSe to form a composite nanostructures in the nanoscale range. The electrochemical properties of the prepared materials were studied by cyclic voltammetry, which revealed that the synthesized material exhibited remarkable electrochemical supercapacitive activity. Moreover, the composite nanostructures showed excellent photocatalytic activity for degradation of phenol and almost 93% of phenol was degraded with good recyclability and stability. According to The International Commission on Illumination (CIE), the synthesized nanomaterial shows blue emission and is suitable for blue LEDs. [ABSTRACT FROM AUTHOR]

We highlight the reported developments of the palladium-catalyzed C–H activation and functionalization of the inactive/unreactive prochiral C(sp3)–H bonds of aliphatic and alicyclic compounds. There exist numerous classical methods for generating contiguous stereogenic centers in a compound with a high degree of stereocontrol. Along similar lines, the Pd(II)-catalyzed, directing group-aided functionalization of inactive prochiral/diastereotopic C(sp3)–H bonds have been exploited to accomplish the stereoselective construction of stereo-arrays in organic compounds. We present a concise discussion on how specific strategies consisting of Pd(II)-catalyzed, directing group-aided C(sp3)–H functionalization have been utilized to generate two or more stereogenic centers in aliphatic and alicyclic compounds. [ABSTRACT FROM AUTHOR]

We report the synthesis of 4‐aryl‐2‐piperidone, 4‐arylpiperidine motifs, antituberculosis molecule Q203 (Telacebec) and its analogues. Direct lactamization of β‐C−H arylated N‐phthaloyl δ‐aminopentanoic acid carboxamides yielded 4‐aryl‐2‐piperidone (4‐aryl‐δ‐valerolactam) scaffolds. The required β‐C−H arylated N‐phthaloyl δ‐aminopentanoic acid carboxamides were assembled via the Pd(II)‐catalyzed, 8‐aminoquinoline‐aided, sp3β‐C−H activation and arylation method. The β‐C−H arylated N‐phthaloyl δ‐aminopentanoic acid carboxamides containing both 8‐aminoquinoline and N‐phthaloyl protecting groups directly underwent the hydrazine‐mediated lactamization to afford 4‐aryl‐2‐piperidones. 4‐Aryl‐2‐piperidone scaffolds were then converted into N‐functionalized 4‐aryl‐2‐piperidones, 4‐arylpiperidines, which are structurally closer to bio‐active 4‐aryl‐ 2‐piperidone and piperidine motifs. A synthetic route for assembling antituberculosis molecule Q203 and its analogues from the corresponding 4‐aryl‐2‐piperidones was also shown. [ABSTRACT FROM AUTHOR]

AbstractChemical warfare agents (CWAs) are the most feared toxic chemicals intended to debilitate the general human population and regional civilians. Therefore, prompt and urgent decontamination is needed to protect millions of lives and the associated hazardous implications. In this present study, our main goal is to evaluate the performance of Zeolite-Alpha and its various metal oxide composites as novel adsorbents for the decontamination of CWA simulants, 2-chloroethyl ethyl sulfide (CEES), and dimethyl methyl phosphonate (DMMP). Synthesized Zeolite-Alpha and their composites were characterized by XRD, FTIR, SEM-EDS, and BET analysis techniques. The CWA simulants’ decontamination (adsorption and desorption) was monitored using GC-FID and GC-MS analysis techniques. A possible reaction mechanism toward the adsorption and destruction of CWA simulants, CEES, and DMMP was also proposed. Nanocrystalline Zeolite-Alpha and its metal oxide composites are powerful adsorbents, and they showed more significant decontamination potential toward the above CWA simulants. The Cr-O-Alpha and Ag-O-Alpha showed promising results (93–98% decontamination) among all other synthesized metal oxide composites. [ABSTRACT FROM AUTHOR]

Conductive polymers are gaining considerable attention as a potential material for supercapacitor electrodes due to their favorable properties. Among these, polyaniline (PANI) stands out as a cost-effective and easy to synthesize, making it a promising candidate for improving energy storage applications. This study presents the synthesis of a hybrid composite consisting of PANI and NiMnO 3 (NMO) perovskite using the chemical oxidative polymerization method. The morphology and structure of the composite were analyzed by using scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. XRD results showed that the addition of NMO transformed the amorphous structure of PANI into a semicrystalline form, leading to enhanced conductivity. SEM images revealed a more uniform and compact structure, with NMO distributed unevenly within the polymer matrix. Optical analysis indicated that a reduction in the band gap of PANI@NMO reached 2.5 eV. N 2 adsorption-desorption measurements confirmed an increase in the surface area and pore volume. The photocatalytic activity of the PANI@NMO nanocomposite was tested by degrading methylene blue (MB) dye under UV/visible light. The nanocomposite showed high efficiency, degrading 87.75% of MB dye after 125 min of irradiation as compared to their counter parts. Additionally, electrochemical tests demonstrated an improved electrochemical performance of the composite due to enhanced crystallinity, increased surface area, and reduced electron-hole recombination rate. These results suggest that the PANI@NMO nanocomposite has great potential for use in supercapacitors and photocatalysis.