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Chemical reactions metathesis

Grigg and coworkers developed bimetallic domino reactions such as the electro-chemically driven Pd/Cr Nozaki-Hiyama-Kishi reaction [69], the Pd/In Barbier-type allylation [70], Heck/Tsuji-Trost reaction/1,3 dipolar cycloaddition [71], the Heck reaction/metathesis [72], and several other processes [73-75]. A first example for an anion capture approach, which was performed on solid phase, is the reaction of 6/1-134 and 6/1-135 in the presence of CO and piperidine to give 6/1-136. Liberation from solid phase was achieved with HF, leading to 6/1-137 (Scheme 6/1.30) [76]. [Pg.382]

Metathesis of ethylene and butylenes to propylene. Another on-purpose route to propylene is metathesis, a chemical reaction that starts with two compounds, involves the displacement of groups from each and produces two new compounds. The application in this case converts ethylene and mixed butylenes to propylene and butene-1. This route could appeal to a company with refinery or olefins plant ethylene and butylenes that both have market values less than propylene, which could be the case in some local markets. [Pg.78]

Metathesis. A chemical reaction involving a double displacement. That is, groups from two different compounds play musical chairs and form two new compounds when the music stops. [Pg.407]

An alternative indirect method of the synthesis of Mg(AlH )2 is the mechano-chemically activated metathesis reaction which was first reported by Dymova et al. [115, 116] according to the following reactions between MgH, AlH and AICI3 during ball milling... [Pg.223]

Four ways in which chemical reactions may be classified are combination, decomposition, single replacement (substitution), and double replacement (metathesis). [Pg.73]

Metathesis, or double decomposition, is one of the main types of chemical reaction, and it takes place between two compounds, consisting merely in an interchange of radicals, the positive radical of the first compound pairing off with the negative radical of the second, and the negative radical of the first pairing off with the positive of the second. Such a reaction involves no change in the valence of any radical concerned. [Pg.105]

The term metathesis literally means to transpose. The term double replacement is often used to describe these reactions because the cations switch places with each other. These are chemical reactions that involve an exchange of positive ions between two compounds and that generally take place between two ionic compounds in an aqueous solution. The driving force that causes these reactions to occur is a decrease in the number of ions from the reactants to... [Pg.242]

One of the three types of metathesis reactions is driven by the production of an insoluble solid. While we are going to go much more in depth about solubility in Chapter 15, there are some basic rules you can learn now that will provide you with more than enough information to predict the products of chemical reactions. These basic rules, usually referred to as solubility rules, are listed in Table 11.5. When reading the chart, keep in mind that all the solutions listed are aqueous solutions (water is the solvent). The term insoluble is not exactly correct. [Pg.243]

Chemical reactions, like the metathesis reaction that produces lead (II) iodide, can occur spontaneously, just like physical processes. It was once believed that only exothermic processes occurred spontaneously however, it has been shown that many endothermic reactions can occur spontaneously as well. Another factor that must be considered when determining the spontaneity of a reaction is entropy. [Pg.419]

Applications of the olefin metathesis reversible chemical reaction, discovered by Phillips Petroleum in the 1960s, were also developed in the subsequent years. By this reaction, Arco produces propylene from ethylene and butene-2 Hercules prepares its plastic, Metton, from dicyclopentadiene and Shell synthesizes its C12-C14 SHOP (Shell Higher Olefin Process) alcohols used for detergents. [Pg.14]

D) Chemical reaction between the solid and solution species to form a different insoluble solid either directly, or by metathesis, or by deposition of a layer of insoluble product on the surface of the original solid. [Pg.104]

Improvements in existing processes accompagnied by new techniques. The first edition of this book presented 70 processes. It now discusses 140. Admittedly these are not all innovations. Many of them are different versions of the same chemical reaction or of an already existing separation method. Others, more innovative, only made headway slowly their industrial penetration was hindered by the slowdown in economic expansion new solvents in extractive distillation for benzene production, metathesis of olefins (Shell), olefins for oxo synthesis (Dimersol, Instituc Franfais du Pitrole), adiponitrile by direct hydrocyanation of butadiene (Dm Pont de Nemours), or by the conversion of 1,6-hexanediol (Celanese), laur IIactam from cyclododecane [ATO, Huls). [Pg.414]

When a compound undergoes a reaction and maintains its molecular structure and thus its identity, the reaction is called a physical reaction. Melting, evaporation, dissolution, and rotation of polarized light are some examples of physical reactions. When a compound undergoes a reaction and changes its molecular structure to form a new compound, the reaction is called a chemical reaction. Combustion, metathesis, and redox are examples of chemical reactions. Chemical reactions can be represented by a chemical equation with the molecular formulae of the reactants on the left and the products on the right. [Pg.12]

We now discuss chemical reactions in further detail. We classify them as oxidation-reduction reactions, combination reactions, decomposition reactions, displacement reactions, and metathesis reactions. The last type can be further described as precipitation reactions, acid-base (neutralization) reactions, and gas-formation reactions. We will see that many reactions, especially oxidation-reduction reactions, fit into more than one category, and that some reactions do not fit neatly into any of them. As we study different kinds of chemical reactions, we will learn to predict the products of other similar reactions. In Chapter 6 we will describe typical reactions of hydrogen, oxygen, and their compounds. These reactions will illustrate periodic relationships with respect to chemical properties. It should be emphasized that our system is not an attempt to transform nature so that it fits into small categories but rather an effort to give some order to our many observations of nature. [Pg.140]

The term metathesis literally means to transpose. The term double replacement is often used to describe these reactions because the cations switch places with each other. These are chemical reactions that involve an exchange of positive ions between two compounds and that generally take place between two ionic compounds in an aqueous solution. The driving force that causes these reactions to occur is a decrease in the number of ions from the reactants to products. This will occur when a stable product forms from the ionic reactants. The three types of stable products that can form are a precipitate (or an insoluble solid), a gas (gaseous materials will bubble out of the solutions and leave the reaction mixture), or a stable molecule (a weak electrolyte, or nonelectrolyte, such as water). A general equation for a double-replacement reaction is... [Pg.247]

Because the chemical reaction used is a simple metathesis or double decomposition of two salts, the reaction vessels can also be simple. An open kettlef with a jacket for temperature control, and a simple stirrer rotating with plenty... [Pg.14]

Olefin metathesis I A chemical reaction in which all of the double bonds in a hydrocarbon molecule are broken and then rearranged. [Pg.64]

Cyclative cleavage strategies (e.g., metathesis and heterocycle ring formation), traceless linkers (e.g., Si, Ge linkers or via chemical reactions such as desulfurization, decarboxylation and cycloreversion) and cleavage steps designed to liberate an increasing diversity of functional groups are illustrated in Section 2.4.4. [Pg.37]

Olefin metathesis is a versatile reaction for the production of fine chemicals. Through metathesis, many different products, which are otherwise difficult to obtain, can be produced from readily available olefins in only a few reaction steps. With heterogeneous catalysts metathesis can be performed under mild reaction conditions and with high selectivity. Metathesis routes that use cheap raw material, such as esters from natural sources, and accessible heterogeneous catalysts are technologically viable. [Pg.573]

Description Two chemical reactions take place in the OCT process propylene is formed by the metathesis of ethylene and butene-2 and butene-1 is isomerized to butene-2 as butene-2 is consumed in the metathesis reaction. [Pg.257]


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See also in sourсe #XX -- [ Pg.116 , Pg.119 ]

See also in sourсe #XX -- [ Pg.97 ]

See also in sourсe #XX -- [ Pg.123 , Pg.123 , Pg.128 , Pg.137 ]




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