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Zinc acetate cyanide

In a related study, Srivastava and Collibee employed polymer-supported triphenyl-phosphine in palladium-catalyzed cyanations [142]. Commercially available resin-bound triphenylphosphine was admixed with palladium(II) acetate in N,N-dimethyl-formamide in order to generate the heterogeneous catalytic system. The mixture was stirred for 2 h under nitrogen atmosphere in a sealed microwave reaction vessel, to achieve complete formation of the active palladium-phosphine complex. The septum was then removed and equimolar amounts of zinc(II) cyanide and the requisite aryl halide were added. After purging with nitrogen and resealing, the vessel was transferred to the microwave reactor and irradiated at 140 °C for 30-50 min... [Pg.377]

In Volume V of this series, syntheses were presented for coordination compounds of 2,2 -iminodipyridine [di-2-pyridylamine, NH(C6H4N)2] with copper(II) and cobalt-(II). Nickel(II) has also been shown to coordinate with this ligand. A similar behavior is exhibited by zinc salts, which form 1 1 derivatives if a 1 1 mol ratio of reactants is used. The specific choice of a solvent medium for synthesis is dictated by the solubility of the zinc compound. Either acetone or methanol may be used with zinc chloride, methanol with zinc acetate, and pyridine with zinc cyanide. [Pg.10]

Magnesium Carbonate Hydroxylamine Hydrochloride Methyl Amyl Alcohol Atropine Sulfate Nitroglycerin Zinc Stearate Zinc Cyanide Zinc Acetate Carbon Tetrabromide Tetrabromomethane Skydrol LD4 Carbon Tetrachloride Tetrachloromethane Methallyl Chloride Silver Acetate Methyl Isopropyl Ketone 3-Methyl-2-Butanone Aminoacetic Acid Glycine... [Pg.1672]

When an organic compound is heated with a mixture of zinc powder and sodium carbonate, the nitrogen and halogens are converted into sodium cyanide and sodium hahdes respectively, and the sulphur into zinc sulphide (insoluble in water). The sodium cyanide and sodium hahdes are extracted with water and detected as in Lassaigne s method, whilst the zinc sulphide in the residue is decomposed with dilute acid and the hydrogen sulphide is identified with sodium plumbite or lead acetate paper. The test for nitrogen is thus not affected by the presence of sulphur this constitutes an advantage of the method. [Pg.1044]

Synthesis of the remaining half of the molecule starts with the formation of the monomethyl ether (9) from orcinol (8). The carbon atom that is to serve as the bridge is introduced as an aldehyde by formylation with zinc cyanide and hydrochloric acid (10). The phenol is then protected as the acetate. Successive oxidation and treatment with thionyl chloride affords the protected acid chloride (11). Acylation of the free phenol group in 7 by means of 11 affords the ester, 12. The ester is then rearranged by an ortho-Fries reaction (catalyzed by either titanium... [Pg.314]

Write the formula for each of the following compounds (a) hydrogen iodide, (b) calcium chloride, (c) lithium oxide, (d) silver nitrate, (e) iron(II) sulfide, (/) aluminum chloride, (g) ammonium sulfate, (h) zinc carbonate, (/) iron(lll) oxide, ( ) sodium phosphate, (k) iron(H) acetate, (/) ammonium cyanide, and (m) copper(II) chloride. [Pg.110]

Muzzarelli and Sipos [622] showed that a column of chitosan (15 x 10 mm) can be used to concentrate zinc from 3 litres of seawater before determination by anodic-stripping voltammetry with a composite mercury-graphite electrode. Zinc (and lead) are eluted from the column by 2 M ammonium acetate (50 ml), copper by 0.01 M EDTA (10 ml), and cadmium by 0.1 M potassium cyanide (3 ml). [Pg.235]

Modifiers in the flotation of sulphide minerals mainly include depressants and activators. A depressant is defined as a reagent which inhibits the adsorption of a collector on a given mineral or adsorbed on the mineral to make the siuface hydrophilic, and includes inorganic depressants such as lime, sodium cyanide, sulphin dioxide, zinc sulphate, sodium sulphide etc., and organic depressants such as sulfhydryl acetic acid, polyacrylamide polymers containing various functional groups etc. In this chapter, roles of depressants in the flotation sulphide minerals will be discussed and some new organic depressants will be introduced. [Pg.112]

The chemistry outlined in Scheme 24 was then put into effect catalytic hydrogenation of the tris-isoxazole (302) and recyclization with triethylamine gave a tricyclic ligand which was chelated with nickel ions to give (303). Introduction of the fourth nitrogen atom was accomplished by treatment of (303) with ammonium acetate, giving (304). Treatment with cyanide removed the nickel ion which was then replaced with zinc(II) to give (305). The reasons for this transmetallation step were two-fold firstly, zinc(II) corrins, as shown by Eschenmoser, can be readily demetallated, and this fact opens up many options later in the synthesis, but secondly, and more importantly, Eschenmoser s photochemical cyclization of seco-corrins (see Section 3.07.3.4.2.3) does not proceed with nickel complexes of seco-corrins, whereas zinc(II) seco-corrins can be cyclized in almost quantitative yield... [Pg.426]

Thiophenecarbaldehydes add smoothly to a,f3-unsaturated ketones and nitriles under cyanide ion catalysis to form y-diketones (366) and y-ketonitriles (367) respectively (76CB534). The 2,5-dicarbaldehyde gives the bis-adduct (368). The aldehydes undergo normal reduction to the hydroxymethylthiophenes by sodium borohydride. However, electrochemical reduction of the 2,5-dialdehyde on a mercury electrode at pH 1-3 gives the bimolecular reduction product (369) as a mixture of meso- and ( )-forms in the ratio 7 3. Reduction with zinc and acetic acid gives only the meso -form of (369) (75CR(C)(280)165>. [Pg.808]

The 2,2 -bipyridylamine complexes of some zinc, cadmium, and mercury salts have been reported.29 All the metal halide complexes isolated are of the stoicheiometry MLX2 (M = Zn, Cd, or Hg X = Cl, Br, or I), and are assigned a monomeric, tetrahedral structure on the basis of i.r. evidence. The complexes ML(SCN)2 (M = Zn, Cd, or Hg) are also monomeric. Only mercuric cyanide reacts to give the monomeric HgL(CN)2, whereas zinc sulphate forms 1 1 and 1 1.5 complexes which possess highly polymeric structures. Zinc and cadmium acetates form 1 1 complexes having pseudo-octahedral structures with bidentate, symmetrically chelating acetates. Cadmium also forms a 1 3 complex which is best formulated as [CdL3] [OAc]2. [Pg.439]

Dechlorination of 4-chloro-6-methylthieno[2,3-d]pyrimidine 164 with zinc in ethanol and acetic acid at 80°C gave compound 165. The latter was subjected to the Reissert reaction using two equivalents each of tributyltin cyanide and acyl chloride in dichloromethane at room temperature. With benzoyl chloride the mono-Reissert adduct 166 was obtained, whereas with acetyl chloride the di-Reissert product 167 (86JHC545). [Pg.229]


See other pages where Zinc acetate cyanide is mentioned: [Pg.89]    [Pg.652]    [Pg.18]    [Pg.47]    [Pg.242]    [Pg.35]    [Pg.352]    [Pg.255]    [Pg.326]    [Pg.161]    [Pg.433]    [Pg.156]    [Pg.14]    [Pg.313]    [Pg.617]    [Pg.210]    [Pg.148]    [Pg.9]    [Pg.180]    [Pg.353]    [Pg.1177]    [Pg.112]    [Pg.400]    [Pg.955]    [Pg.202]    [Pg.53]    [Pg.210]    [Pg.22]    [Pg.400]    [Pg.955]    [Pg.156]    [Pg.223]   
See also in sourсe #XX -- [ Pg.1087 ]




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Zinc cyanide

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