Bismuth synthesis

Early catalysts for acrolein synthesis were based on cuprous oxide and other heavy metal oxides deposited on inert siHca or alumina supports (39). Later, catalysts more selective for the oxidation of propylene to acrolein and acrolein to acryHc acid were prepared from bismuth, cobalt, kon, nickel, tin salts, and molybdic, molybdic phosphoric, and molybdic siHcic acids. Preferred second-stage catalysts generally are complex oxides containing molybdenum and vanadium. Other components, such as tungsten, copper, tellurium, and arsenic oxides, have been incorporated to increase low temperature activity and productivity (39,45,46). 

Quaternary bismuth compounds have not found extensive use ia industry or ia organic synthesis. In manifold studies of organobismuth(V) compounds as oxidi2ing and arylating agents, such quaternary bismuth compounds as (CgH )4Bi02CCH2, (CgH )4Bi02SCgH4CH2-4, and... 

Bismuth heterocycles, 1, 539-561 Bismuthiol I metal complexes, 6, 565 IR spectra, 6, 552 ring structure, 6, 561 structure, 6, 557 Bismuthiol II metal complexes, 6, 565 IR spectra, 6, 552 Bisnorisopenicillin, 7, 332, 333 Bisnorpenicillin V, 7, 331 Bis( l,3,4-oxathiazol-2-ones) applications, 6, 945 Bisoxiranes synthesis, 7, 42 Bi(spiroisoxazolines) synthesis, 6, 108 Bi(spirophosphoranes) polytopal rearrangements, 1, 529 reactions, 1, 535 Bispyranones synthesis, 3, 793 a,oj-Bispyranones, alkylene-irradiation, 3, 678... 

Another example of the use of neutron diffraction to understand the role of atomic vacancies in producing a superconducting metal oxide phase is work that has been performed on Bao Kq 4fii03. This work demonstrates that at the synthesis temperature (700° C), under the proper conditions, oxygen vacancies are created to allow the formation of the parent phase with bismuth largely in the +3 oxidation state. The presence of the vacancies allows the incorporation of potassium in the... 

Bismuth(V) oxide and bismuthates are even less well established though a recent important development has been the synthesis and structural characterization of LisBiOs, prepared by heating an intimate mixture of Li20 and Q -Bi203 at 650° for 24 h in dry O2. The structure is of the defect rock-salt type with an ordering of... 

Bismuth(III) acetate catalyzes the synthesis of azlactones (17) from aromatic aldehydes in moderate to good yields via the Erlenmeyer synthesis. While the standard procedure for azlactone synthesis consists of using a stoichiometric amount of fused anhydrous sodium acetate, 10 mol% of Bi(OAc)3 is sufficient to catalyze the reaction and the crude product is found to be > 98% pure. 

As described earlier one of the possible products from the AFO reaction is dihydroxyflavonols. Simpson and coworkers took advantage of this outcome in their synthesis of the flavonol rhamnocitrin (23). Chalcone 24 was subjected to the typical AFO conditions to deliver dihydroxyflavonol 25. The isolated product was further subjected to hydrogen peroxide to afford flavonol 25a in 30% yield. However, treatment of 25 with bismuth acetate, generated in situ from bismuth carbonate and acetic acid, gave 25a in 77% yield for a respectable 52% overall yield over two steps. 25a was then selectively demethylated with anilinium chloride to deliver rhamnocitrin (23). 

Barton and co workers have explored the aryladon of various nucleophiles inclndmg nitroalkanes using bismuth reagents Reacdon of 2-nitropropane v/ith triphenylbismnth carbonate gives 2-nitro-2-phenylpropane in 80% yield Recently, this aryladon has been used for the synthesis of unusual amino acids Aryladon of ct-nitro esters v/ith triphenylbismnth dichloride followed by redncdon gives unique ct-amino acids fEq 5 68 ... 

Write a nuclear equation for each of the following transformations (a) 25 Rf produced by the bombardment of califomium-245 with carbon-12 nuclei (b) the first synthesis of 266Mt by the bombardment of bismuth-209 with iron-58 nuclei. Given that the first decay of meitnerium is by a emission, what is the daughter nucleus ... 

But first the synthesis had to come John was interested in reduced metal halides, particularly for the post-transition metals cadmium, galHum, and bismuth (his Ph.D. dissertation was on anhydrous aluminum halides and mixed halide intermediates, a good start for what was to come ). However, he was not yet actively interested in rare-earth metals and their remarkable solubility in their halides. But these elements lured him one floor below where Adrian Daane headed the metallurgy section of Spedding s empire. He knew how to produce rare-earth metals with high purity and in sufficient quantity and also how to handle tantalum containers. What if one gave it a tr/ and reduced some rare-earth metal halides (John insists that this term is used correctly) from their respective metals at high temperatures under appropriate conditions. 

Menke EJ, Brown MA, Li Q, Hemminger JC, Penner RM (2006) Bismuth telluride (Bi2Te3) nanowires Synthesis by cyclic electrodeposition/stripping, thinning by electrooxidation, and electrical power generation. Langmuir 22 10564-10574... 

Scheme 11.4 shows some other representative Friedel-Crafts acylation reactions. Entries 1 and 2 show typical Friedel-Crafts acylation reactions using A1C13. Entries 3 and 4 are similar, but include some functionality in the acylating reagents. Entry 5 involves formation of a mixed trifluoroacetic anhydride, followed by acylation in 85% H3PO4. The reaction was conducted on a kilogram scale and provides a starting material for the synthesis of tamoxifen. Entry 6 illustrates the use of bismuth triflate as... 

Allylation of acyloyl-imidazoles and pyrazoles61 with allyl halide mediated by indium in aqueous media provides a facile regioselective synthesis of P, y-unsaturated ketones (Scheme 11.1), which has been applied to the synthesis of the monoterpene artemesia ketone. The same product can be obtained by indium-mediated allylation of acyl cyanide (Eq. 11.35).62 Samarium, gallium, and bismuth can be used as a mediator for the allylation of nitrones and hydrazones to give homoallylic hydroxylamine and hydrazides in aqueous media in the presence of Bu4NBr (Scheme 11.2).63 The reaction with gallium and bismuth can be increased dramatically under microwave activation. 

The origin of chemical elements has been explained by various nuclear synthesis routes, such as hydrogen or helium burning, and a-, e-, s-, r-, p- and x-processes. "Tc is believed to be synthesized by the s (slow)-process in stars. This process involves successive neutron capture and / decay at relatively low neutron densities neutron capture rates in this process are slow as compared to /1-decay rates. The nuclides near the -stability line are formed from the iron group to bismuth. 

Recently, nanocomposites of calcium and bismuth mixed oxides obtained by flame synthesis were used for the degradation of organic dyes under visible light, with good activity due to the formation of relatively high surface area materials and oxygen vacancy formation in the flame process [119]. 

Sardar, K., Playford, H.Y., Darton, R.J., Barney, E.R., Hannon, A.C., Tompsett, D., Fisher, J., Kashtiban, R.J., Sloan, J., Ramos, S., Cibin, G. and Walton, R.I. (2010) Nanocrystalline cerium-bismuth oxides synthesis, structural characterization, and redox properties. Chemistry of Materials, 22 6191-6201. 

Synthesis and Reactivity of Conjugated and Nonconjugated Rings Containing Arsenic, Antimony, and Bismuth... 

CHEC-II(1996) comprehensively outlines the most commonly used synthetic approaches applied to these types of bicyclic compounds of phosphorus, arsenic, antimony, and bismuth <1996CHEC-II(8)863>. The six classes of compounds listed in this section have received considerable attention over the review period and as such the principal synthetic methods for these compounds are discussed. Schoth et al. <2000CCR101> have reviewed the use of fluorinated 1,3-diketones, 2-trifluoroacetylphenols, and their derivatives in the synthesis of phosphorus compounds. Included in this review is the use of these reagents for the synthesis of various [3.3.1] nonfused and [3.3.0] fused phosphorus bridgehead bicyclic systems. 

A number of new conditions and catalysts have been used for the synthesis of quinazolinones 50 from anthranilic acids, amines and ortho esters, including bismuth trifluoroacetate with an ionic liquid <06TL3561>, lanthanum nitrate or tosic acid under solvent-free conditions at room temperature <06TL4381> and Nafion-H <06SL2507>. 

The synthesis of stable complexes with transition metal-phosphorus triple bonds is of fundamental importance and opens a novel chapter of a special field of coordination chemistry. The synthesis of analogous complexes with ligands of the heavier homologues like arsenic has partially been carried out [6], while for antimony and bismuth, the elusive M=Sb and M=Bi systems have now moved within reach. Moreover, the experimental and theoretical... 

Hur et al. (252,277,278) reported the use of alkali metal-doped MgO to catalyze the synthesis of acrylonitrile and propionitrile (278). Acrylonitrile is an important chemical, especially in the polymer industry it is generally synthesized by the ammoxidation of propene catalyzed by multicomponent bismuth molybdates (279). An alternative method of synthesis of acrylonitrile is the reaction between methanol and acetonitrile (Scheme 42). 

One of the simplest examples for such effects is the oxidation of ammonia with iron oxide-bismuth oxide as a catalyst. Here, the addition of bismuth oxide results in the formation of nitrous oxides as the main product whereas an iron oxide catalyst without bismuth oxide yields nitrogen almost exlcusively. Selectively guiding catalysts become increasingly important in the synthesis of organic compounds, e.g., in the hydrogenation of carbon monoxide where the type of obtainable product can be varied, within wide limits, by the kinds of catalysts and promoters which are employed. 

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