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CuS, synthesis

Copper (Cu) Synthesis of hemoglobin Food supply Toxicity is very rare, deficiency - anemia excess - liver and kidney 1.5 to 3.0 mg... [Pg.122]

Ghosh T, Leonard BM, Zhou Q, DiSalvo FJ (2010) Pt alloy and intermetallic phases with V, Cr, Mn, Ni, and Cu synthesis as nanomaterials and possible applications as fuel cell catalysts. Chem Mater 22 2190-2202... [Pg.86]

Catalytic-in-Cu synthesis of indoles was reported by Yamanaka [187], Villemin [188], Yamamoto (Scheme 9.38) [189], and then Cacchi (Scheme 9.39) [190]. In contrast to the previous examples, no loss of the TMS-group was observed under these reaction conditions. [Pg.342]

The technique of low-energy electron diffraction, LEED (Section VIII-2D), has provided a considerable amount of information about the manner in which a chemisorbed layer rearranges itself. Somotjai [13] has summarized LEED results for a number of systems. Some examples are collected in Fig. XVlII-1. Figure XVIII-la shows how N atoms are arranged on a Fe(KX)) surface [14] (relevant to ammonia synthesis) even H atoms may be located, as in Fig. XVIII-Ih [15]. Figure XVIII-Ic illustrates how the structure of the adsorbed layer, or adlayer, can vary wiA exposure [16].f There may be a series of structures, as with NO on Ru(lOTO) [17] and HCl on Cu(llO) [18]. Surface structures of... [Pg.686]

An organozmc compound that occupies a special niche m organic synthesis is lodo methyhinc iodide (ICH2ZnI) It is prepared by the reaction of zinc-copper couple [Zn(Cu) zinc that has had its surface activated with a little copper] with diiodomethane m diethyl ether... [Pg.604]

A convenient synthesis of organochlorosilanes from organosilanes is achieved by reaction with inorganic chlorides of Hg, Pt, V, Cr, Mo, Pd, Se, Bi, Fe, Sn, Cu, and even C. The last compounds, tin tetrachloride, copper(II) chloride, and, under catalytic conditions, carbon tetrachloride (117,118), are most widely used. [Pg.27]

It has been seen that this resin has also some important advantages over the other resins in the literature like high total ion exchange capacity, easy synthesis, lower cost, simple regeneration. Furthermore, very good sepai ations were obtained using a concentration gradient of elution. In these elutions, very low concentrations of sodium trimetaphosphate were used. As a result, the resin synthesized can be used as an adsorbent for the effective removal of Pb, Cd, Co, Cu, Fe, Ni, Zn and Cr from aqueous solutions. [Pg.289]

Soild-8quld phase transfer catalyst 2 (or aliphatic and arematic nudeophiftc substitution also synergistic effect with Cu in UHmann synthesis. [Pg.356]

ULLMANN GOLDBERG Aromatic substitution Cu catalyzed substitution of aromatic halides in the synthesis of disryls, diaiyl ethers, diaryl amines, phenols... [Pg.395]

Copper (I) thiophenolate [1192-40-1] M 172.7, m ca 280°, pKj 6.62 (for PhS ). The Cu salt can be extracted from a thimble (Soxhlet) with boiling MeOH. It is a green-brown powder which gives a yellow-green soln in pyridine. Wash with EtOH and dry in a vacuum. It can be ppted from a pyridine soln by addition of H2O, collect ppte, wash with EtOH and dry in a vacuum. [Synthesis 662 1974, J Am Chem Soc 79 170 1957-, Chem Ber 90 425 1957.]... [Pg.414]

Figure 7 Microanalysis of a CuO/ZnO methanol synthesis catalyst with a field-emission STEM (a) EOS data showing Cu and Zn K-lines and (b) EELS data showing Cu and Zn L-edges with dotted lines indicating background levels. Spectra were taken simultaneously from a 2-nm diameter area. Signal intensities above background show that approximately the same relative amounts of Cu and Zn were measured by each method. Figure 7 Microanalysis of a CuO/ZnO methanol synthesis catalyst with a field-emission STEM (a) EOS data showing Cu and Zn K-lines and (b) EELS data showing Cu and Zn L-edges with dotted lines indicating background levels. Spectra were taken simultaneously from a 2-nm diameter area. Signal intensities above background show that approximately the same relative amounts of Cu and Zn were measured by each method.
The influence of Zn-deposition on Cu(lll) surfaces on methanol synthesis by hydrogenation of CO2 shows that Zn creates sites stabilizing the formate intermediate and thus promotes the hydrogenation process [2.44]. Further publications deal with methane oxidation by various layered rock-salt-type oxides [2.45], poisoning of vana-dia in VOx/Ti02 by K2O, leading to lower reduction capability of the vanadia, because of the formation of [2.46], and interaction of SO2 with Cu, CU2O, and CuO to show the temperature-dependence of SO2 absorption or sulfide formation [2.47]. [Pg.24]

Apparently, aminobutenyne A, the intermediate of the pyrrole synthesis, is fixed in an advantageous eonfiguration by eoordination to the Cu eation, whereas the absenee of eatalyst may result in the formation of imine B having an aetive methylene group whieh attaeks the aeetylene bond to form dihydropyridine C and then pyridine 2 (by dehydrogenation). [Pg.160]

This methodology has been used for the synthesis of the C3-C14 segment 24 of the antitumor agent laulimalide 23 (Scheme 4.22) [35]. The constrained chiral BOX ligand 21c in combination with Cu(OTf)2 afforded dihydropyrane 6f by a cycloaddition reaction in good yield and ee this was converted to the C3-C14 segment 24 via a Ferrier-type rearrangement in several steps. [Pg.169]

Yosida et al. [41] found that p-t< rr-butylcalix[6]ar-ene can extract Cu from the alkaline-ammonia solution to the organic solvent. Nagasaki and Shinkai [42] described the synthesis of carboxyl, derivatives of calix-[n]arenes ( = 4 and 6) and their selective extraction capacity of transition metal cations from aqueous phase to the organic phase. Gutsche and Nam [43] have synthesized various substituted calix[n]arenes and examined the complexes of the p-bromo benzene sulfonate of p-(2-aminoethyl)calix[4]arene with Ni, Cu , Co-, and Fe. ... [Pg.342]

As inert as the C-25 lactone carbonyl has been during the course of this synthesis, it can serve the role of electrophile in a reaction with a nucleophile. For example, addition of benzyloxymethyl-lithium29 to a cold (-78 °C) solution of 41 in THF, followed by treatment of the intermediate hemiketal with methyl orthoformate under acidic conditions, provides intermediate 42 in 80% overall yield. Reduction of the carbon-bromine bond in 42 with concomitant -elimination of the C-9 ether oxygen is achieved with Zn-Cu couple and sodium iodide at 60 °C in DMF. Under these reaction conditions, it is conceivable that the bromine substituent in 42 is replaced by iodine, after which event reductive elimination occurs. Silylation of the newly formed tertiary hydroxyl group at C-12 with triethylsilyl perchlorate, followed by oxidative cleavage of the olefin with ozone, results in the formation of key intermediate 3 in 85 % yield from 42. [Pg.245]

Although these methods were applied for the synthesis of a number of various phthalocyanines with different central atoms (e.g., H2, Cu, Zn, Ni, Pt, Pd, Lu, etc.) not all metal phthalocyanines can be prepared by one of these methods. For example, the synthesis of silicon phthalocyanine, rhenium phthalocyanine and boron subphthalocyanine need more drastic conditions. In the following, an overview of the synthesis of phthalocyanines containing all central metals which have hitherto been inserted into the ring is given. [Pg.727]

A novel use of a chlorofluorocarbon is in the synthesis of a pyrone (30) from 1,1,1-trichlorotrifluoroethane. The key step involves Cu(I) catalysis. Pyrone (30) is a useful CF3 aromatic synthon, as it readily underwent (4 + 2) cycloaddition followed by spontaneous elimination of C02 (85-TL3947). [Pg.17]

Since the mid-1990s, synthetic attention has been directed more towards the use of metal-stabilized nitrenes as synthetic effectors of alkene aziridination. In 1969 it was reported that Cu(i) salts were capable of mediating alkene aziridination when treated with tosyl azide, but the method was limited in scope and was not adopted as a general method for the synthesis of aziridines [12]. Metaloporphyrins [13] were shown to be catalysts for the aziridination of alkenes in the presence of the nitrene precursor N-tosyliminophenyliodinane [14] in the early 1980s, but the reaction did... [Pg.122]

Terpenoid substances are of broad distribution and diverse function in insects. One set, elaborated by the mandibular glands of Acanthomyops claviger, acts both as a defensive secretion and as an alarm releaser. When fed Cu-labeled acetate or mevalonate, laboratory colonies of these ants produce radioactive citronellal and citral, providing unambiguous evidence for de novo synthesis of these terpenes by the ant. The incorporations of these precursors implicate the mevalonic acid pathway as the likely biosynthetic route. [Pg.31]

By using a cocatalyst of Pd-Cu, aryl-alkenyl halides couple efficiently widi alkynes to generate die disubstituted alkynes (Scheme 9.6).8 This coupling reaction has been applied to die synthesis of polyphenyleneethynylenes by Yamamoto et al. in 1984 (Scheme 9.7).9a Due to the ready availability of diacetylenes and the mild coupling condition, this strategy has been widely used for die preparation of many poly(aryleneethynylene)s.9... [Pg.468]


See other pages where CuS, synthesis is mentioned: [Pg.339]    [Pg.419]    [Pg.213]    [Pg.10]    [Pg.339]    [Pg.419]    [Pg.213]    [Pg.10]    [Pg.209]    [Pg.293]    [Pg.450]    [Pg.20]    [Pg.316]    [Pg.438]    [Pg.491]    [Pg.442]    [Pg.259]    [Pg.68]    [Pg.171]    [Pg.86]    [Pg.94]    [Pg.331]    [Pg.136]    [Pg.207]    [Pg.667]    [Pg.79]    [Pg.89]    [Pg.68]   


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