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Zirconiums reactions with

Ghalcogenides. The reactions of pure zirconium turnings with threefold quantities of elemental sulfur, selenium, or tellurium give ZrS ... [Pg.434]

Zirconium tetrachloride is instantly hydrolyzed in water to zirconium oxide dichloride octahydrate [13520-92-8]. Zirconium tetrachloride exchanges chlorine for 0x0 bonds in the reaction with hydroxylic ligands, forming alkoxides from alcohols (see Alkoxides, METAl). Zirconium tetrachloride combines with many Lewis bases such as dimethyl sulfoxide, phosphoms oxychloride and amines including ammonia, ethers, and ketones. The zirconium organometalLic compounds ate all derived from zirconium tetrachloride. [Pg.435]

Zirconium monochloride and zirconium monobromide [31483-18-8] are prepared in better purity by equiUbration of mixed lower haUdes with zirconium foil at 625°C (184—185) or by slowly heating zirconium tetrahaUde with zirconium turnings at 400—800°C over a period of two weeks and hoi ding at 800—850°C for a few additional days (186). Similar attempts to produce zirconium monoiodide [14728-76-8] were unsuccesshil it was, however, obtained from the reaction of hydrogen iodide with metallic zirconium above 2000 K (187). [Pg.436]

Alkoxides can be formed also by reaction of zirconium dialkylarnines with alcohols, and alkoxides can be exchanged also be transesterification reactions. [Pg.438]

Photochlorination of tetrachloroethylene, observed by Faraday, yields hexachloroethane [67-72-1]. Reaction with aluminum bromide at 100°C forms a mixture of bromotrichloroethane and dibromodichloroethane [75-81-0] (6). Reaction with bromine results in an equiUbrium mixture of tetrabromoethylene [79-28-7] and tetrachloroethylene. Tetrachloroethylene reacts with a mixture of hydrogen fluoride and chlorine at 225—400°C in the presence of zirconium fluoride catalyst to yield l,2,2-trichloro-l,l,2-trifluoroethane [76-13-1] (CFG 113) (7). [Pg.28]

Alkyds. Alkyd resins (qv) are polyesters formed by the reaction of polybasic acids, unsaturated fatty acids, and polyhydric alcohols (see Alcohols, POLYHYDRic). Modified alkyds are made when epoxy, sUicone, urethane, or vinyl resins take part in this reaction. The resins cross-link by reaction with oxygen in the air, and carboxylate salts of cobalt, chromium, manganese, zinc, or zirconium are included in the formulation to catalyze drying. [Pg.365]

The lithium salt of 2-(di-wo-propylamino)-l,2-thiaborolide with [( -Cp ) RuC1]4 or [(i -Cp )ZrCl3] yields sandwiches similar to 39 (M = Ru, ZrCl2) (OOOM4935). The same anionic ligand enters a sequence of reactions with dimethylchlorosilane, lithium cyclopentadienyl, lithium di-wo-propylamide, and zirconium(IV) chloride to give sandwich 41. [Pg.19]

The reactions of various 2-butenyltitanium and -zirconium reagents with 2-(benzyloxy)propanal (and other O-protected derivatives) also proceed with low induced diastereoselectivity90. [Pg.418]

Though the element was discovered in 1789 it was not prepd in the pure state until 1914. It may be prepd commercially by the reaction of zirconium chloride with magnesium (the Kroll process) and other methods. The principle ore is zircon, deposits of which are found in the USA, Australia and Brazil. A number of special properties, such as exceptional resistance to corrosion and a low absorption cross section, have led to the use of Zr or alloys contg Zr, in many... [Pg.979]

With diphosphanes recently Stephan et al. reported an intriguing Al and P based macrocyclic structure [37]. A zirconium based catalyst precursor first was employed in the catalytic dehydrocoupling of the primary bidentate phosphane to give the tetraphosphane 6, (Scheme 4). The function of 6 as a molecular building block has been demonstrated by its reaction with MMe3(M = Al, Ga). Although, the gallium derivative 7 has not been... [Pg.92]

Numerous other reactions can be used to access phosphaalkenes. For example, treating the primary phosphine Mes PH2 with CH2CI2 in the presence of KOH gives Mes P=CH2 [54]. In addition, interesting reactions of tantalum-or zirconium-phosphinidenes with aldehydes have afforded phosphaalkenes [55, 56]. The 1,3-hydrogen rearrangement of secondary vinylphosphines to phosphaalkenes has also been used to prepare phosphaalkenes [57,58]. [Pg.112]

Reaction products of a zirconium halide with sorbitol and citric, malic, or lactic acids [1495]... [Pg.258]

The above reaction shows that the oxychloride decomposes at the sublimation temperature into the volatile tetrachloride and the nonvolatile oxide. Reduction starts as soon as the chloride vapour contacts the molten magnesium, and this exothermic reaction raises the temperature of the reaction mixture. The temperature of the reduction crucible is maintained in the range of 800 to 875 °C. The process is carefully controlled by matching the sublimation rate of zirconium tetrachloride with the reduction rate. The conclusion of the reduction is indicated by a fall in temperature and pressure. [Pg.418]

After extraction, the loaded solvent contains 6 g T1 zirconium as zirconium oxide with 0.2% hafnium oxide. The raffinate is left with 0.2 to 0.3 g l l of the oxides of zirconium and hafnium of this, 70-90% is hafnium oxide. This raffinate can act as a feed solution for the recovery of pure hafnium oxide. The loaded extractant, on the other hand, is subjected to a scrubbing operation with pure zirconium sulfate solution to eliminate any co-extracted hafnium. This scrubbing operation is essentially a displacement reaction ... [Pg.526]

One method of solving the kinetics dilemma is well known in coordination chemistry that is, start with a labile metal ion and render it inert during the course of the synthetic reaction. We have accomplished this in the case of zirconium(IV) by starting with tetrakis(salicylaldehydo)zirconium(IV), which is quite labile, and polymerization with 1,2,4,5-tetraaminobenzene in a Schiff-base condensation reaction in situ (6). The polymeric product contains a "double-headed" quadridentate ligand, which is much more inert to substitution. However, 1,2,4,5-tetraaminobenzene has become very expensive. Therefore, the synthesis of a zirconium polymer with 3,3, 4,4 -tetraaminobiphenyl (commercially 3,3 -diami nobenzidine) with zirconium salicylaldehyde, Zr(sal)4 (7) has been undertaken as shown below ... [Pg.464]


See other pages where Zirconiums reactions with is mentioned: [Pg.284]    [Pg.137]    [Pg.430]    [Pg.438]    [Pg.53]    [Pg.92]    [Pg.499]    [Pg.439]    [Pg.171]    [Pg.613]    [Pg.187]    [Pg.257]    [Pg.336]    [Pg.13]    [Pg.14]    [Pg.76]    [Pg.168]    [Pg.232]    [Pg.290]    [Pg.455]    [Pg.226]    [Pg.945]    [Pg.72]    [Pg.185]    [Pg.192]    [Pg.193]    [Pg.196]    [Pg.1857]    [Pg.1925]    [Pg.371]    [Pg.341]    [Pg.136]   


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3- indene, reaction with zirconium

Carbon monoxide reaction with zirconium compounds

Reduction reactions with zirconium

Zirconium complexes reactions with isocyanates

Zirconium oxide reaction with, phosgene

Zirconium reagents, allylic reaction with carbonyl compounds

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