Solid zirconium chlorides

Diammino-zirconium Tetrachloride, [Zr(NH3)2]Cl4, is prepared by passing dry ammonia gas over solid zirconium tetrachloride at ordinary temperature.2 The compound is a fine white powder which readily loses ammonia in moist air, and is decomposed by water with formation of zirconium hydroxide, Zr(OII)4, and ammonium chloride. At higher temperatures more ammonia is absorbed, and tetrammino-zirconium tetrachloride, [Zr(NH3)4]Cl4, is formed. 

Mix together on a spot plate 2 drops each (equal volumes) of a 0-1 per cent aqueous solution of alizarin-S (sodium alizarin sulphonate) and zirconyl chloride solution (0-1 g solid zirconyl chloride dissolved in 20 ml concentrated hydrochloric acid and diluted to 100 ml with water) upon the addition of a drop or two of the fluoride solution the zirconium lake is decolourized to a clear yellow solution. 

A dimeric zirconium(IV) trihydride complex has been synthesized by reaction of LiBHEt3 with the tridentate triaryloxide zirconium chloride complex ZrCl(THF)2(t-Bu-L) (H3(t-Bu-L) = 2,6-bis(4-t-butyl-6-methylsalicyl)-4-f-butylphenol) (equation 14). The solid-state structure shows each zirconium center adopts a trigonal prismatic stracture with a Zr-Zr separation of 3.163(1) A. In solution, the three resulting hydrides appear equivalent on the NMR timescale. Analogous reactivity was observed for the titanium conger. However, in the resulting titanium trihydride, the metals are assigned formal Ti(III) oxidation states. ... 

Recently one of the solutions to overcome this problem has been proposed.This does concern surface modification of the pyrochlore-based oxide.s. It is known that cerium and zirconium chlorides provide vapor phase complexes with aluminum chloride at elevated temperatures.The new surface modification technique utilizes the formation of these vapor complexes to remove and modify the top surface of the pyrochlore ceria-zirconia solid solution. This method is named "chemical filing". Application of the above complexes formation has already been demonstrated for the vapor phase extraction and mutual separation of rare earths based on the so-called chemical vapor transport (CVT). ... 

ZrCl4 ZIRCONIUM CHLORIDE 44.472 5.0671E-01 -1.1887E-03 1.2934E-06 -5.3834E-10 298 710 solid... 

EINECS 233-058-2 HSDB 2531 Tetrachlorozirconium UN2503 Zirconium chloride Zirconium chloride (ZrCU) Zirconium chloride, tetra- Zirconium tetrachloride Zirconium(IV) chloride (1 4). Source of the pure metal, analytical chemistry, water repellents for textiles, tanning agent, zirconium compounds, special catalysts (Friedel-Crafts, Ziegler). Solid mp = 437 d = 2.8030 LDso (rat orl) = 1588 mg/kg. Cerac, 3973Afomergic Chem Chemetals Noah. 

Synonyms Zirconium chloride Zirconium (IV) chloride Zirconium (IV) chloride (1 4) Zirconium tetrachloride solid... 

Zhang, J. (1990). Solid State Chemistry of Centered Zirconium Chloride Clusters. Synthesis and Characterization of New Compounds, Ph.D. Dissertation, Iowa State University. 

Ziebarth, R. P. Corbett, J. D. (1989a). Centered Zirconium Chloride Clusters. Synthetic and Structural Aspects of a Broad Solid-State Chemistry, Acc. Chem. Res. 22, 256-262. 

Mixed Chloride-Iodide Zirconium Cluster Phases with a 6 18 Metal Halide Ratio -Products from Solid-state Reactions... 

In order to obtain compounds with Ti-O-P and Zr-O-P units, the hexaethoxy-derivative, NsPaCOEOg, was treated with titanium and zirconium tetrachlorides. In each case, hygroscopic solids of the type NaPaCOEOiOaMCU (M = Ti or Zr) and ethyl chloride were obtained. The degree of polymerization of these solids was 1.6—1.8, and on the basis of their i.r. and n.m.r. spectra, two alternative structures, (46) and (47), were proposed. In an alternative route to the same type of compound, N3P3CI6 was treated with tetra-n-butoxytitanium in o-xylene. Butyl chloride was liberated and a solid was obtained which has been assigned the structure (48). Its thermal decomposition was studied by differential thermal analysis. 

Zirconium(IV) and hafnium(IV) chlorides and bromides form 1 2 adducts of the type [ZrX4(RCN)2] (R = Me, Et, Pr or Ph X = Cl or Br) and [HfX4(MeCN)2] (X = Cl or Br).11SM24 These complexes may be prepared by (i) direct reaction of the metal tetrahalide with an excess of the nitrile120 123 or (ii) electrochemical oxidation of zirconium or hafnium metal in the presence of a solution of chlorine or bromine in acetonitrile.118 The adducts are moisture-sensitive, white solids, insoluble in nonpolar solvents, but soluble in acetonitrile. In the later solvent, [ZrBr4(MeCN)2 behaves as a nonelectrolyte.122... 

Zirconium(IV) chloride reacts with P(NCO)3 in benzene and with P(CN)3 in benzene-diethyl ether to give the substitution products ZrCl3 P(NCO)2 and ZrCl3 P(CN)2, respectively (equation 25). These compounds have been obtained as somewhat impure, very hygroscopic solids. On the basis of IR evidence, the P(NCO)2 and P(CN)2 ligands are believed to be coordinated through the phosphorus atom.138... 

Subsequently, the same authors138 described the preparation of a solid superacid catalyst with acid strength of H0 = —16 with a sulfuric acid-treated zirconium oxide. They exposed Zr(OH)4 to 1A sulfuric acid and calcined it in air at approximately 600°C. The obtained catalyst was able to isomerize (and crack) butane at room temperature. The acidity was examined by the color change method using Hammett indicators added to a powdered sample placed in sulfuryl chloride. The... 

Syntheses of MPc from phthalodinitrile or phthalic anhydride in the presence of urea are the two most important laboratory and industrial methods. They were also used originally by Linstead et al. [8,9], This procedure allows the production of many phthalocyanine compounds [35-37], Catalysts such as boric acid, molybdenum oxide, zirconium and titanium tetrachloride, or ammonium molybdate are used to accelerate the reaction and improve the yield [36,37], Ammonium molybdate is especially effective. Reaction is carried out either in a solvent or by heating the solid components. When metal chlorides and phthalodinitrile are used as starting materials, the reaction products are partially chlorinated (e.g.,7). 

In all of the discussion of this chapter we have used an aqueous solution as the electrolyte, and electrodes suitable to those aqueous solutions. However, cells are not limited to aqueous solutions. Indeed, other solvents have been used for which liquid ammonia would be an example. Molten salts, such as mixtures of lithium chloride and potassium chloride, have been used for the study of cells at high temperatures. Some studies have been made at higher temperatures, in which solid electrolytes were used. Electrodes compatible with such solvents have also been devised. For example, a zirconium-zirconium oxide electrode stabilized with calcium oxide was used to measure the oxygen potential in nonstoichiometric metal oxides. However, no matter what the electrolytes or the electrodes are, the principles discussed in this chapter such as reversibility and proper measurement must be followed. 

Excision reactions are sometimes accompanied by redox chemistry. For example, dissolution of the 2D solid Na4Zr6BeCli6 in acetonitrile in the presence of an alkylammonium chloride salt results in simultaneous reduction of the cluster cores (144). Here, the oxidation product remains unidentified, but is presumably the solvent itself. As a means of preventing such redox activity, Hughbanks (6) developed the use of some room temperature molten salts as excision media, specifically with application to centered zirconium-halide cluster phases. A number of these solids have been shown to dissolve in l-ethyl-2-methylimidazolium chloride-aluminum chloride ionic liquids, providing an efficient route to molecular clusters with a full compliments of terminal chloride ligands. Such molten salts are also well suited for electrochemical studies. 

Zirconium tetrachloride is a white crystalline solid with specific gravity 2.803.4 The solid sublimes under atmospheric pressure at 331° [log pBin. = — (26,000/4.57T) + 12.30] but melts at 437° under its own pressure, which is about 25 atm. at this temperature.18 The vapor density shows normal behavior up to 500°, at which point dissociation is suspected.16 Electron-diffraction results show tetrahedral symmetry with the Zr-Cl distance 2.33 A.17 Todd18 has recently determined the heat capacity of zirconium tetrachloride at low temperatures (extrapolated below —222°) and calculated the usual thermodynamic constants for the compound. The melting point of hafnium tetrachloride has been estimated as 432° under its own pressure, but the solid sublimes under atmospheric pressure at 317°.12 Both metal chlorides are extremely hygroscopic. They are easily soluble in water, although extensively hydrolyzed. All high-purity samples should be desiccated as well as possible. 

In an argon atmosphere 40 ml of toluene containing the Step 1 product (5.65 mmol) was added to a 40 ml of the toluene solution containing tetrakis(dimethylamino) zirconium (5.77 mmol) and then refluxed for 4 hours. The mixture was concentrated and treated with 80 ml of toluene containing trimethylsilyl chloride (92.3 mmol) and stirred overnight. The mixture was re-concentrated, and the residue was washed with pentane and extracted with CH2CI2. The extract was then concentrated, and precipitated crystals were collected by fdtration. Crystals were washed with diethyl ether and dried under reduced pressure at from 70°C to 120°C. The crystals were re-extracted with methylene chloride, the solution concentrated, and 0.2 g of a clear yellow solid product was isolated. 

In an application of the Paal-Knorr pyrrole synthesis, the synthetic equivalents 3 of 1,4-ketoaldehydes were prepared by the radical addition of ketones 4 to vinyl pivalate. Treatment of the intermediates 3 with amines gave pyrroles 5 <03SL75>. Other new extensions of this popular pyrrole synthesis include the preparation of a number of pyrroles from hexane-2,5-dione and amines under solvent-free conditions in the presence of layered zirconium phosphate or phosphonate catalysts <03TL3923>, and the development of a solid-phase variant of this reaction <03SL711>. Likewise, the preparation of iV-acylpyrroles from primary amides and 2,5-dimethoxytetrahydrofuran in the presence of one equivalent of thionyl chloride has also been reported <03S1959>. 

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