Copper ultrasonic irradiation

Lack of cooling during preparation of the Simmons-Smith organozinc reagent caused the reaction to erupt. The possibly pyrophoric nature of organozinc compounds and the presence of ether presents a severe fire hazard [1]. An alternative, safer method of activating the zinc for the reaction involves use of ultrasonic irradiation rather than the copper-zinc couple [2]. 

In a second round-bottomed flask, dissolve the iodide (100 mg, 0.23 mmol) and methylvinylketone (0.17 mL, 2 mmol) in ethanol (2.1 mL) and water (0.9 mL). Add this solution to the zinc-copper couple via a syringe, under sonication, and continue ultrasonic irradiation for 35 min. 

USAL has also been used in the determination of trace impurities in high-purity materials. This type of analysis is mandatory with a view to controlling their quality and studying the synergistic action of, and correlation with, impurities. The accuracy and precision of the analytical results depend strongly on the particular separation procedure used before the determination step, as shown in the multi-element quantitative USAL of impurities such as iron, copper, lead and bismuth in high-purity silver metal. For this purpose, a silver sample was dissolved in nitric acid and treated with chloride, after which the solution was evaporated to dryness and the impurities were redistributed on the surfaces or in the interstitial spaces of agglomerates of matrix crystals. Then, the impurities were leached into 0.1 M nitric acid with the aid of ultrasonic irradiation [91]. 

Such a reaction of Fe(CO)5 (at 293-363 K, PVP) without ultrasonic radiation proceeds very slowly and only after few days there, a material is formed with very low Fe content (2%, the isolated particles 2-5 nm in size). It is of interest that the sonochemical decomposition of Fe(CO)5 does not proceed in the presence of PVP if THF is used as the solvent, but the reaction is very effective when anisole is used as the solvent and PFO is used as the polymer matrix [93]. A black product formed contains up to 10% (in mass) of the spheric particles of nonoxidized Fe (mainly y-Fe, with little content of a-Fe) with 1-12 nm in size (the mean diameter is 3nm, as shown in Figure 3.7). It is likely that the big particles present the flocks of little ones ( 2-2.5nm). The sonochemical synthesis allows us to produce the functionalized amorphous nanoparticles of ferric oxide with 5-16 nm in diameter [94]. The ultrasonic irradiation in the PFO presence allows us to also produce the stabilized nanoparticles of copper, gold, and so on. In the literature the findings are not about the bimetallic particle formation in the ultrasonic fields by carbonyl metal reduction in the polymer matrices presence (as, for example, in the case of the carbon-supported Pt-Ru from PtRu5C(CO)i6 reduced clusters [95]). 

Park et al. [61] synthesized ZnO-CuO core-branch hybrid NPs by copper oxide growth and controlled oxidation on ZnO nanospheres, and exhibited remarkable enhancement of catalytic activity and stability for ultrasound-assisted [3+2] azide-alkyne cycloaddition reactions imder ultrasonic irradiation (Scheme 5.19). The surface species of the catalysts were investigated by XPS with the core level of Cu 2p3 2 before and after the reaction. The peaks are deconvoluted into two peaks, where the peak at lower binding energy is attributed to Cu(l) and that at higher binding energy is attribnted to the Cu(ll) species. Before the reaction, the... 

The solvent-free potassium permanganate promoted oxidation of alcohols into the corresponding carbonyl derivatives has been examined by Luu et al. (2008). Secondary alcohols were oxidized very efficiently to the corresponding ketones at ambient temperature by KMnO absorbed on a fourfold molar amount of copper (II) sulfate pentahydrate. The reaction rate was enhanced considerably by ultrasonic irradiation also, but drastically in the presence of microwave irradiation, may be due... 

There is little reported data on ultrasonic synthesis of metal chelates [738-740]. Interaction between metallic copper or nickel with azomethinic ligands in ethanol, dioxane, or various lubricant oils (10% solution) was studied in Ref. 738. After 4 hr of US irradiation of the reaction mixture, the formed complexes 829 (R = Ph, CH3, H, Cl, N02 M = Ni, Cu) were isolated with yields of 10-25%, in dependence on metal and ligand nature ... 

Beads of mass 5-10 mg were first cleaned ultrasonically, as required. They were stored individually in 1.2 mL polyethylene vials, were irradiated serially for five minutes at a neutron flux of 1.0 10 neutrons.cm. sec. Five to seven minutes after irradiation, the induced radioactivity was counted for five minutes using a hyper-pure germanium detector-based gamma-ray spectrometer. This produced analytical concentration data for cobalt (Co), tin (Sn), copper (Cu), sodium (Na), aluminium (Al), manganese (Mn), chlorine (Cl) and calcium (Ca). The samples were recounted for five to thirty-three minutes the next day to measure the concentrations of the longer-lived radioisotopes of Na, arsenic (As),... 

Ziarati et al. [69] developed the synthesis of compounds with pharmaceutical and biological properties. Thus, 2-aryl-5-methyl-2,3-dihydro-lH-3-pyrazolones (72) were synthesized via a four-component reaction of ethyl acetoac-etate (66), hydrazine (67), aldehyde (69), and p-naphthol (70) in water under ultrasound irradiation with a multiwave ultrasonic generator in the presence of nanoparticles of copper iodide as catalyst, using a simple preparation protocol (Scheme 17). It should be mentioned that the catalyst could be recycled and reused for five times without evidently... 

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