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Zinc Compounds iodide

Metal-containing compounds, Zinc Compounds (Continued) (Carboethoxyalkyl)zinc iodide, 220 (Carboethoxyethyl)zinc iodide, 220 (Carboethoxypropyl)zinc iodide, 220 Chlorotrimethylsilane-Zinc, 82 (Cyanomethyl)zinc bromide, 221 Dibromomethane-Zinc-Copper(I) chloride, 93... [Pg.416]

Palladium catalysed coupling reaction of a heteroaromatic zinc compound with a functionalized aryl iodide preparation of N-benzyl-6-(4-ethylcarboxyphenyi)-purine33... [Pg.205]

Less work had been done with zinc compounds, but enough to indicate a contrast with lithium and magnesium derivatives. For example, perfluoro-n-propyl zinc iodides [50, 51] and perfluoroisopropyl zinc iodides [22] can be obtained, and the n-propyl derivative is even stable in dioxane at reflux. It should be noted that these compounds are stable largely because they are solvated and it has not been possible to remove the solvent completely. Zinc under these circumstances appears to be a very strong acceptor and therefore the compounds decompose much more readily when formed in the free state [52] (Figure 10.12). [Pg.371]

The less stable trifluoromethyl zinc compounds [48] can be used as a source of nucleophilic trifluoromethyl fragments either in the isolated form or generated in situ by sonication of perfluoroalkyl iodides with zinc in DMF or THF. Zinc perfluoroorganyls find application in Barbier-type reactions [49], palladium-catalyzed cross-coupling reactions [50], or hydroperfluoroalkylations of acetylenes or olefins [51] (Scheme 2.119). [Pg.106]

Very. similar behaviour has been reported [292] when zinc atoms are co-condensed with a number of fluoroalkyl iodides at —196°C, the zinc atom inserting into the carbon—iodine bond. The resultant non-solvated fluoro-organic zinc compounds have properties vastly different from those generated by conventional solution-phase techniques, being much more reactive and less stable. It was also shown that methyl iodide and trifluoromethyl bromide are much less reactive towards zinc atoms than is trifluoromethyl iodide. [Pg.229]

The addition of diorganozinc compounds to alkynes can be promoted by different metallic species such as Cp2Zrl2 and Ni(acac)2 to give the corresponding vinylic zinc compounds (equation 72). A subsequent hydrolysis leads to the alkene, whereas iodinolysis provides the vinyl iodide derivative. Copper-zinc species, readily obtained by the... [Pg.5238]

The reaction takes place more rapidly in the presence of a small quantity of ethyl acetate or methyl cyanide, or when the zinc-copper couple is used. Zinc ethyl iodide is a colorless, crystalline solid, which is decomposed by water, and reacts with many compounds that contain a halogen or oxygen. The decomposition in the case of water is represented by the equation,—... [Pg.369]

Perfluoroalkylacetylenes 4 are prepared from olefins 2 (Rp = perfluoroalkyl) by exhaustive chlorination under ultraviolet irradiation, followed by treatment with zinc. The resulting acetylenic zinc compounds 3 are decomposed by dilute hydrochloric acid. 1,1-Dibromoalk-l-enes 5 (R = Me, cyclohexyl etc. R = H or Ph) are converted into the rearranged acetylenes 7 by the action of samarium(II) iodide in benzene containing 10% HMPA alkylidenecarbenes 6 are presumed to be intermediates in this process. ... [Pg.288]

Also Pdotalyzed Negishi cross-coupling reactions have been described in ionic liquids. Knochel and coworkers investigated the reaction between organometalhc zinc compounds and aryl iodide in [BMMIM][Bp4] using an ionic phosphine ligand. Scheme 5.3-30 illustrates the reaction for the formation of a 3-substituted cyclohexenone from 3-iodo-cyclohex-2-en-l-one [170]. The reaction vras carried out in an ionic liquid/toluene biphasic system, which allowed easy product recovery from the catalyst by decantation. However, attempts to recycle the ionic catalyst phase resulted in significant catalyst deactivation, after only the third recycle. [Pg.430]

Shaw and co-workers used a mixed Lewis acid approach to synthesize chiral furanmethanol derivatives from glycals. These compounds are important intermediates in the synthesis of many biologically significant compounds and serve as precursors for furanmethanes and 3-acylfurans. Reaction of a selectively protected 6-azido glycal with zirconium(IV) chloride and zinc(II) iodide gave the desired chiral furan selectively in 74% yield. [Pg.150]


See other pages where Zinc Compounds iodide is mentioned: [Pg.318]    [Pg.366]    [Pg.351]    [Pg.115]    [Pg.115]    [Pg.98]    [Pg.25]    [Pg.108]    [Pg.227]    [Pg.5180]    [Pg.351]    [Pg.63]    [Pg.633]    [Pg.896]    [Pg.366]    [Pg.226]    [Pg.15]    [Pg.117]    [Pg.1762]    [Pg.2025]    [Pg.70]    [Pg.5179]    [Pg.8]    [Pg.8]    [Pg.324]    [Pg.1116]    [Pg.226]   
See also in sourсe #XX -- [ Pg.280 ]




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Zinc compounds

Zinc iodide

Zinc iodide benzylic compounds

Zinc iodide carbonyl compounds

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