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1,3-Diketones, metal derivatives

These substances [/9-diketonate metal derivatives] may be represented by formulae [/] and [III], from which it will be seen that structural isomerism... [Pg.37]

The same principles determine bond formation in the complexes formed by the )5-diketones. The ability of diketones to form metallic derivatives is determined by the extent of enolization, e,g. [Pg.390]

The methods of preparation and purification of metal derivatives of 1,3-diketones have been described in a previous volume. Because of the interest in the structure " and reactions of metal derivatives of /3-keto imines, RC0CH2C(=NR )R", it is desirable to consider the methods of preparation of these compounds. Inasmuch as /3-keto imines are closely related to 1,3-diketones and to salicylaldimines, o-HOC6H4CH==NR, the methods of preparation show similarities. Although this review is concerned principally with /3-keto imines, some comparisons with 1,3-diketones and salicylaldimines are made. [Pg.46]

Direct Combination of a 1,3-Diketone, an Amine, and a Metal Ion. Direct combination is a potentially useful reaction, and it has been used to prepare metal-salicylaldimine compounds. The procedure consists of mixing (and refluxing if necessary) a stoichiometric mixture of salicylaldehyde with an amine, a metal ion, and a base in dilute aqueous methanol. This procedure has not been applied commonly to the preparation of metal derivatives of jS-keto imines, although the preparation of 4,4 -(ethylene-dinitrilo)di-2-pentanonatocopper(II) from 2,4-pentanedi-one (acetylacetone), ethylenediamine, and copper has been described. Attempts to effect condensation of 1,1,1,5,5,5-hexafluoro-2,4-pentanedione (hexafluoroacetylacetone) and ethylenediamine by direct combination of the reactants in the presence of copper(II) acetate were imsuccessful. ... [Pg.49]

Interaction of a Soluble -Keto Imine Salt and a Soluble Metal Salt. The syntheses of a number of metal derivatives of 1,3-diketones are representative of this method, but the extension to metal jS-keto imines has been limited to the synthesis of chromium (III) derivatives. These have been prepared by the interaction of trichlorotris-(tetrahydrofuran)chromium(III) and the potassium salt of a /3-keto imine. (See synthesis 38.)... [Pg.50]

The many satisfactory procedures which have been published for the preparation of metal derivatives of 2,4-pen-tanedione (acetylacetone) are not always successful when applied to other 8-diketones. Thus, poor yields of impure product are obtained with attempts to prepare the... [Pg.135]

Back in 1899, Werner and Stiasny (49) had studied the action of nitric acid on azobenzene and produced a series of nitro-azobenzenes and nitro-azoxybenzenes, but Werner carried the work no further. Werner then became interested in the analogy between the lakes of mordant dyes and the metallic derivatives of /3-diketones and proposed the view that mordant dyes were internal metallic complexes. This resulted in three papers published in the 1908-09 period. The first (43) reporting the complex metal salts formed from oximes, diketones, and several metals, came to the conclusion that the formation of mordant dyes depends on the formation of complex metal salts. He found that dyes capable of combining with mordants possessed both a salt-forming complex and a group capable of forming a coordinate link with a metal ion. [Pg.93]

Metal diketonates, the salts of /3-diketones and /3-ketoimines, are of interest for their usefulness as reagents (principally the alkali metal derivatives) and as potential precursors (the alkaline-earth derivatives) for CVD. The latter are discussed in additional detail in Section 3.1.4.4.1(vi), and Group 2 /3-diketonates used for this purpose have been extensively reviewed.Considerable interest has been expressed in fluorinated derivatives, which can display substantially increased volatility relative to the hydrocarbon compounds. Commonly used /3-diketones and /3-ketoimines... [Pg.53]

This method is applicable to the preparation of a wide variety of metal derivatives. Mixed metal halide diketonates are generally obtained with the less electropositive elements like B, Si, Ge, Sn, Ti, P, Sb, Nb, Ta, due to steric constrains in the coordination environment, sometimes with formation of ionic species (Equation (13)) or with excess of starting metal halide (Equation (14)) ... [Pg.105]

Carbonates of Be, Ca, Sr, Ba, Zn, Co, and TI react with diketones in refluxing alcohol or water-alcohol mixtures, producing the metal derivatives and C02. [Pg.105]

The 2-diazo-1,3-diketones (14) react with titanocene precursors affording l-titana-2, -dihetero-cyclic complexes.102 2-(2-thiazolylazo)- 1,3-diketones (15) and their corresponding metal derivatives have also been synthesized.103... [Pg.109]

See also Preparation of metal derivatives of 1,3-diketones, synthesis 29 Dichloro(di-2-pyridylamine)cobalt(II), synthesis 50... [Pg.14]

The structures, types, properties, uses, nomenclature, and general methods of preparation of metal derivatives of 1,3-diketones have been discussed in a previous volume.1 It now seems desirable to consider in somewhat more detail the various factors involved in the preparation and purification of these substances. [Pg.105]

Preparation of Metal Derivatives of 1,3-Diketones. Methods of preparation may be grouped into several general classes. [Pg.105]

The effect of the limited water solubility of a 1,3-diketone can also be overcome by dissolving the compound in a water-immiscible organic solvent and then shaking with an aqueous solution of a salt of the appropriate metal.9,12,13 Ideally, this procedure necessitates one of two situations (i) insolubility of the metal derivatives in water and in the immiscible solvent or (it) complete extraction of the product into the immiscible solvent (see 3 below). If such conditions do not prevail, the solids must be removed by filtration and the solvent evaporated. Because neither (i) nor (it) is encountered in most cases, procedures which assume that one or the other prevails often give low yields. [Pg.106]

Reaction of a 1,3-Diketone with a Metal Oxide, Hydroxide, Carbonate, or Basic Carbonate, a. In Aqueous Solution. The reaction between a 1,3-diketone and a suspension of a hydrous oxide or hydroxide,36 although often slow, may present the advantage of introducing minimum amounts of impurity. Furthermore, this procedure permits the preparation of metal derivatives in oxidation states that are relatively unstable under other conditions. [Pg.108]


See other pages where 1,3-Diketones, metal derivatives is mentioned: [Pg.233]    [Pg.233]    [Pg.71]    [Pg.11]    [Pg.140]    [Pg.251]    [Pg.372]    [Pg.241]    [Pg.309]    [Pg.2934]    [Pg.711]    [Pg.98]    [Pg.99]    [Pg.99]    [Pg.103]    [Pg.107]    [Pg.110]    [Pg.111]    [Pg.111]    [Pg.58]    [Pg.43]    [Pg.105]    [Pg.107]   
See also in sourсe #XX -- [ Pg.2 , Pg.6 , Pg.10 , Pg.11 , Pg.12 , Pg.13 , Pg.14 , Pg.15 , Pg.16 , Pg.105 , Pg.106 , Pg.107 , Pg.108 , Pg.109 , Pg.110 , Pg.111 , Pg.112 ]

See also in sourсe #XX -- [ Pg.2 , Pg.6 , Pg.10 , Pg.11 , Pg.12 , Pg.13 , Pg.14 , Pg.15 , Pg.16 , Pg.105 , Pg.106 , Pg.107 , Pg.108 , Pg.109 , Pg.110 , Pg.111 , Pg.112 ]




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1.3- Diketones, derivatives

1.3- Diketones, metal derivatives structure

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Metallic derivates

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