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Reactions with Zinc

When acetic anhydride is used in the CF3CCI3 and zinc reaction with aldehydes, the initial addition product undergoes an elimination reaction to give 2-chloro-l,l,l-trifluoro-2-alkenes exclusively [60, 63] (equation 51)... [Pg.681]

Figure 6. Soluble Zinc Reaction With Silica... Figure 6. Soluble Zinc Reaction With Silica...
One of the most readily observed reactions in chemistry is the familiar production of bubbles of a colourless gas when certain metals (for example, iron, zinc) react with dilute acids. Cavendish investigated these reactions rather more than 200 years ago, and found the gas evolved to be the same in each case the gas, later named hydrogen, was much lighter than air and when burned in air produced water. [Pg.111]

Despite its electrode potential (p. 98), very pure zinc has little or no reaction with dilute acids. If impurities are present, local electrochemical cells are set up (cf the rusting of iron. p. 398) and the zinc reacts readily evolving hydrogen. Amalgamation of zinc with mercury reduces the reactivity by giving uniformity to the surface. Very pure zinc reacts readily with dilute acids if previously coated with copper by adding copper(II) sulphate ... [Pg.417]

When the reaction is complete, heat the stirred mixture carefully under reflux over a Bunsen burner and asbestos gauze for I hour if the mixture becomes too thick for efficient stirring, add up to 15 mL of acetic acid. Now decant the hot mixture into 500 ml. of vigorously-stirred ice-cold water wash the residual zinc thoroughly with glacial acetic acid (2 portions each of I -2 ml.), decanting the acid also into the stirred water. [Pg.294]

Reaction with 3 5-dinitrobenzoyl chloride. Ethers undergo cleavage with 3 5 dinitrobenzoyl chloride in the presence of zinc chloride ... [Pg.315]

Both cis- and irans- 1,2-dibromoethylenes react with metal acetylides, but with different reactivity. For the competitive reaction of cis- and trans- fl-dibromoethylenes with the zinc acetylide 314 shows that the irans isomer is more reactive than the cis isomer[228,229]. It was also found by a competitive reaction with the zinc acetylide 317 that the irans vinyl monobromide 315 is more reactive than the cis isomer 316[230]. [Pg.173]

The terminal diyne 320 is prepared by coupling of the zinc acetylide 318 with /rfln.s-l-iodo-2-chloroethylenc (319), followed by elimination of HCI with sodium amide[231]. Similarly, terminal di- and triynes are prepared by using cw-l,2-dichloroethylene[232]. The 1-alkenyl or l-aryl-2-(perefluoroalkyl) acetylene 321 is prepared by the reaction of a zinc acetylide with halides[233]. [Pg.173]

Chemical ingenuity in using the properties of the elements and their compounds has allowed analyses to be carried out by processes analogous to the generation of hydrides. Osmium tetroxide is very volatile and can be formed easily by oxidation of osmium compounds. Some metals form volatile acetylacetonates (acac), such as iron, zinc, cobalt, chromium, and manganese (Figure 15.4). Iodides can be oxidized easily to iodine (another volatile element in itself), and carbonates or bicarbonates can be examined as COj after reaction with acid. [Pg.100]

Raw Material. PVA is synthesized from acetjiene [74-86-2] or ethylene [74-85-1] by reaction with acetic acid (and oxygen in the case of ethylene), in the presence of a catalyst such as zinc acetate, to form vinyl acetate [108-05-4] which is then polymerized in methanol. The polymer obtained is subjected to methanolysis with sodium hydroxide, whereby PVA precipitates from the methanol solution. [Pg.337]

For reaction with hydrogen haUdes, the substitution reaction with haUde ion easily occurs when a cuprous or cupric compound is used as the catalyst (23) and yields a halogenated aHyl compound. With a cuprous compound as the catalyst at 18 °C, the reaction is completed in 6 h. Zinc chloride is also a good catalyst (24), but a by-product, diaHyl ether, is formed. [Pg.73]

The order of reactivity with acid is HI > HBi > HCl. Reaction with hydrochloric acid [7647-01-0] to form isopropyl chloride [75-29-6] is faciUtated by a zinc chloride catalyst. [Pg.105]

Zinc oxide is a common activator in mbber formulations. It reacts during vulcanization with most accelerators to form the highly active zinc salt. A preceding reaction with stearic acid forms the hydrocarbon-soluble zinc stearate and Hberates water before the onset of cross-linking (6). In cures at atmospheric pressure, such as continuous extmsions, the prereacted zinc stearate can be used to avoid the evolution of water that would otherwise lead to undesirable porosity. In these appHcations, calcium oxide is also added as a desiccant to remove water from all sources. [Pg.225]

Lubrication of sheet and strip is necessary for aU operations. Although for special operations vegetable and mineral oUs maybe employed, a mixture of paraffin and taUow oU is normally preferred in rough rolling. Requirements for finish-roll lubricant are more strict because of staining caused by breakdown of the oU or reaction with the zinc. Strip zinc is usuaUy finish-rolled with cotton seed or mineral oU. [Pg.414]

Reactions with zinc or aluminum are typically carried out in hydrocarbon solvents. Many of the methyknetal derivatives undergo protonolysis or oxidation very readily, and must be protected from exposure to air or water. [Pg.294]

Reactivities of several chlorinated solvents, including chloroform, with aluminum, iron, and 2inc in both dry and wet systems have been deterrnined, as have chemical reactivities in oxidation reactions and in reactions with amines (11). Unstabilized wet chloroform reacts completely with aluminum and attacks zinc at a rate of >250 //m/yr and iron at <250 //m/yr. The dry, uiiinhibited solvent attacks aluminum and zinc at a rate of 250 )J.m/yr and iron at 25 ]lni / yr. [Pg.525]

Dehalogenation of monochlorotoluenes can be readily effected with hydrogen and noble metal catalysts (34). Conversion of -chlorotoluene to Ncyanotoluene is accompHshed by reaction with tetraethyl ammonium cyanide and zero-valent Group (VIII) metal complexes, such as those of nickel or palladium (35). The reaction proceeds by initial oxidative addition of the aryl haHde to the zerovalent metal complex, followed by attack of cyanide ion on the metal and reductive elimination of the aryl cyanide. Methylstyrene is prepared from -chlorotoluene by a vinylation reaction using ethylene as the reagent and a catalyst derived from zinc, a triarylphosphine, and a nickel salt (36). [Pg.53]


See other pages where Reactions with Zinc is mentioned: [Pg.827]    [Pg.839]    [Pg.149]    [Pg.44]    [Pg.346]    [Pg.37]    [Pg.100]    [Pg.113]    [Pg.260]    [Pg.130]    [Pg.295]   


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Addition Reactions with Copper-Zinc Reagents

Allylic chlorides, reaction with zinc-copper

Chlorophosphines, reaction with zinc

Copper ions reactions with zinc metal

Diethyl zinc, reaction with carbenes

Dimethyl zinc, reaction with

Dimethyl zinc, reaction with cobalt

Dimethyl zinc, reaction with cobalt complexes

Enones reaction with zinc ester enolates

Grignard reagent zinc halide reaction with

Hydrochloric acid reaction with zinc

Hydrochloric acid reaction with zinc sulfide

Hydrogen chloride zinc reaction with dissolved form

Hydrogen chloride, reaction with zinc

Iodine reaction with zinc

Iodoethane, reaction with zinc

Iodomethane reaction with zinc

Ketones, reaction with zinc borohydride

Lithium salt of 2- -l,2thiaborolide, reaction with ruthenium and zinc complexes

Nitric acid reaction with zinc

Oxygen reaction with zinc sulfide

Propionic acid, a-bromoethyl ester reaction with zinc

Reaction with zinc metal

Reactions with Aryl Zinc Compounds

Reactions with zinc ester dieneolates

Reactions with zinc ester dienolates

Reactions with zinc oxide

Silver® ions, reaction with zinc

Substitution Reactions with Copper-Zinc Reagents

Substitution reactions asymmetric, with zinc compounds

Substitution reactions with zinc compounds

Sulfur reaction with zinc

With zinc

Zinc alkyls reactions with

Zinc aryls reactions with

Zinc chloride, reaction with phenylmagnesium bromide

Zinc cyanide reaction with aromatic compounds

Zinc diethyl-: Simmons-Smith reaction with

Zinc ester enolates reaction with conjugated enones

Zinc halides reactions with

Zinc hydrides reactions with

Zinc oxide reaction with, phosgene

Zinc oxide reactions with propylene

Zinc reaction

Zinc reaction with hydrochloric

Zinc, arylchlorocoupling reactions with alkenyl bromides

Zinc, bis hydride donor reaction with phenyl isopropyl ketone

Zinc, bis reaction with benzaldehyde

Zinc, bromo reaction with alkynes

Zinc, chloro-2-furylcoupling reactions with alkenyl iodides

Zinc, diethylSubject reaction with 1,2-diketones

Zinc, diethylSubject reaction with benzaldehyde

Zinc, homoallylcoupling reactions with aromatic halides

Zinc, homopropargylcoupling reactions with aromatic halides

Zinc, organo- reagents reactions with

Zinc, propargylreactions with aldimines Knoevenagel reaction

Zinc, reaction with alkyl halides

Zinc-copper reagents reactions with acid chlorides

Zinc—carbon bonds reactions with

Zinc—copper reactions with

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