6 research outputs found
Tin(IV)-Porphyrin Tetracarbonyl Cobaltate: An Efficient Catalyst for the Carbonylation of Epoxides
No full textCationic tin(IV) porphyrins with tetracarbonyl cobaltates were synthesized, exhibiting bifunctional catalytic reactivity. The Lewis acidic tin-porphyrin center activated epoxides; concurrently, cobalt carbonyl anions efficiently opened epoxides and delivered carbonyl moieties. Thus, a series of β-lactones with a high synthetic value were obtained. This catalytic system showed excellent efficiency exceeding a turnover number of one thousand with a broad substrate scope. In addition, the presented tin porphyrin-based catalyst exhibited exclusive chemoselectivity to terminal epoxides over internal ones. The selective carbonylation of di-epoxides demonstrated the usefulness of these catalysts in the synthesis of complex molecular structures
Green Synthesis of Silver Nanoparticles Using <i>Artemisia vulgaris</i> Extract and Its Application toward Catalytic and Metal-Sensing Activity
No full textNonessential heavy metals are toxic to human health. In this study, mercury, a hazardous metal, was detected by colorimetric analysis using Artemisia vulgaris-mediated silver nanoparticles (AgNP) without any modification in an aqueous solution. The UV–vis spectroscopy showed a characteristic SPR band of Ag0 at 418 nm, indicating the formation of AgNPs. The AgNPs were crystalline, with an average size of 7 nm, as calculated from the XRD data. The SEM images revealed the spherical and polycrystalline AgNPs within the agglomerated form. The FTIR spectra elucidated the functional group of the extract attached with the Ag0. The broad, strong peak at 3632 cm−1 indicated the involvement of the -OH group of compounds of extract in reducing silver ions. The peak of EDX spectra around 3 keV confirmed the silver in the nanostructure. A colorimetric method was employed for the heavy metal sensing in the aqueous medium without modification of AgNPs suspension. The obtained AgNPs were found to be selective and highly sensitive toward Hg2+ ions. The AgNPs suspension turned colorless after adding 380 µL of 1 mM Hg2+. The synthesized AgNPs showed the catalytic activity on reduction of 4-nitrophenol in the presence of NaBH4 within 8 min with a rate constant of 1.21 × 10−2 s−1. The outcome of these findings suggests that the application of Artemisia vulgaris influenced AgNPs for metal sensing and green catalysis
Green Synthesis of Silver Nanoparticles Using Artemisia vulgaris Extract and Its Application toward Catalytic and Metal-Sensing Activity
No full textNonessential heavy metals are toxic to human health. In this study, mercury, a hazardous metal, was detected by colorimetric analysis using Artemisia vulgaris-mediated silver nanoparticles (AgNP) without any modification in an aqueous solution. The UV–vis spectroscopy showed a characteristic SPR band of Ag0 at 418 nm, indicating the formation of AgNPs. The AgNPs were crystalline, with an average size of 7 nm, as calculated from the XRD data. The SEM images revealed the spherical and polycrystalline AgNPs within the agglomerated form. The FTIR spectra elucidated the functional group of the extract attached with the Ag0. The broad, strong peak at 3632 cm−1 indicated the involvement of the -OH group of compounds of extract in reducing silver ions. The peak of EDX spectra around 3 keV confirmed the silver in the nanostructure. A colorimetric method was employed for the heavy metal sensing in the aqueous medium without modification of AgNPs suspension. The obtained AgNPs were found to be selective and highly sensitive toward Hg2+ ions. The AgNPs suspension turned colorless after adding 380 µL of 1 mM Hg2+. The synthesized AgNPs showed the catalytic activity on reduction of 4-nitrophenol in the presence of NaBH4 within 8 min with a rate constant of 1.21 × 10−2 s−1. The outcome of these findings suggests that the application of Artemisia vulgaris influenced AgNPs for metal sensing and green catalysis
Stem Bark-Mediated Green Synthesis of Silver Nanoparticles from <i>Pyrus pashia</i>: Characterization, Antioxidant, and Antibacterial Properties
No full textThe investigation of using medicinal plants for the production and application of silver nanoparticles (AgNPs) has attracted growing research interest. In this study, AgNPs are synthesized from the stem barks of the Pyrus pashia medicinal plant using a biosynthetic strategy. The reaction conditions were optimized under ambient conditions, including concentration, temperature, time, and pH, and various techniques were employed, such as UV-visible, FTIR, XRD, FESEM, and TEM, to characterize the synthesized AgNPs. The AgNPs produced through this biosynthesis method were found to be spherical and polydispersed, with an average size of 23.92 ± 7.04 nm. The synthesized AgNPs demonstrated an enhanced DPPH free radical scavenging capacity compared to the aqueous extract, with IC50 values of 10.67 ± 0.05 µg/mL and 13.66 ± 0.35 µg/mL, respectively. In the agar well diffusion method, the synthesized AgNPs showed higher antibacterial activity than that of the extract against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Salmonella typhi (ATCC 14028), and Shigella sonnei (ATCC 25931). Based on these findings, the study suggests that green synthesized AgNPs from P. pashia could be used for biomedical applications
