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(Cyclopentadienyl)zirconium Trichloride
(Cyclopentadienyl)zirconium trichloride is an organozirconium compound with the formula (CH)ZrCl. It a moisture-sensitive white solid. The compound adopts a polymeric structure. The compound has been well studied spectroscopically. Synthesis and reactions It is prepared by chlorination of zirconocene dichloride. Being polymeric, complex is insoluble in nonpolar solvents. It dissolves in the presence of basic ligands to give adducts. See also *(Cyclopentadienyl)titanium trichloride (Cyclopentadienyl)titanium trichloride is an organotitanium compound with the formula (CH)TiCl. It is a moisture sensitive orange solid. The compound adopts a piano stool geometry. Preparation and reactions is prepared by the reaction of tita ..., which exists as a monomer. References {{DEFAULTSORT:Cyclopentadienyl)zirconium trichloride Zirconium(IV) compounds Chloro complexes Organozirconium compounds Cyclopentadienyl complexes Coordination polymers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organozirconium Compound
Organozirconium chemistry is the science of exploring the properties, structure, and reactivity of organozirconium compounds, which are organometallic compounds containing chemical bonds between carbon and zirconium. Organozirconium compounds have been widely studied, in part because they are useful catalysts in Ziegler-Natta polymerization. Comparison with organotitanium chemistry Many organozirconium compounds have analogues on organotitanium chemistry. Zirconium(IV) is more resistant to reduction than titanium(IV) compounds, which often convert to Ti(III) derivatives. By the same token, Zr(II) is a particularly powerful reducing agent, forming robust dinitrogen complexes. Being a larger atom, zirconium forms complexes with higher Coordination number, coordination numbers, e.g. polymeric [CpZrCl3]n vs monomeric (Cyclopentadienyl)titanium trichloride, CpTiCl3 (Cp = C5H5). History Zirconocene dibromide was prepared in 1953 by a reaction of the cyclopentadienyl magnesium bromide an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer
A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compound (chemistry), compounds, produces unique physical property, physical properties including toughness, high rubber elasticity, elasticity, viscoelasticity, and a tendency to form Amorphous solid, amorphous and crystallization of polymers, semicrystalline structures rath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zirconocene Dichloride
Zirconocene dichloride is an organozirconium compound composed of a zirconium central atom, with two cyclopentadienyl and two chloro ligands. It is a colourless diamagnetic solid that is somewhat stable in air. Preparation and structure Zirconocene dichloride may be prepared from zirconium(IV) chloride-tetrahydrofuran complex and sodium cyclopentadienide: :ZrCl4(THF)2 + 2 NaCp → Cp2ZrCl2 + 2 NaCl + 2 THF The closely related compound Cp2ZrBr2 was first described by Birmingham and Wilkinson. The compound is a bent metallocene: the Cp rings are not parallel, the average Cp(centroid)-M-Cp angle being 128°. The Cl-Zr-Cl angle of 97.1° is wider than in niobocene dichloride (85.6°) and molybdocene dichloride (82°). This trend helped to establish the orientation of the HOMO in this class of complex. Reactions Schwartz's reagent Zirconocene dichloride reacts with lithium aluminium hydride to give Cp2ZrHCl Schwartz's reagent: :(C5H5)2ZrCl2 + 1/4 LiAlH4 → (C5H5)2ZrHCl + 1/4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adduct
In chemistry, an adduct (; alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all components. The resultant is considered a distinct molecular species. Examples include the addition of sodium bisulfite to an aldehyde to give a sulfonate. It can be considered as a single product resulting from the direct combination of different molecules which comprises all atoms of the reactant molecules. Adducts often form between Lewis acids and Lewis bases. A good example is the formation of adducts between the Lewis acid borane and the oxygen atom in the Lewis bases, tetrahydrofuran (THF): or diethyl ether: . Many Lewis acids and Lewis bases reacting in the gas phase or in non-aqueous solvents to form adducts have been examined in the ECW model. Trimethylborane, trimethyltin chloride and bis(hexafluoroacetylacetonato)copper(II) are examples of Lewi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(Cyclopentadienyl)titanium Trichloride
(Cyclopentadienyl)titanium trichloride is an organotitanium compound with the formula (CH)TiCl. It is a moisture sensitive orange solid. The compound adopts a piano stool geometry. Preparation and reactions is prepared by the reaction of titanocene dichloride Titanocene dichloride is the organotitanium compound with the formula (hapticity, ''η''5-C5H5)2TiCl2, commonly abbreviated as Cp2TiCl2. This metallocene is a common reagent in organometallic and organic synthesis. It exists as a bright red solid t ... and titanium tetrachloride: : The complex is electrophilic, readily forming alkoxide complexes upon treatment with alcohols. Reduction of (cyclopentadienyl)titanium trichloride with zinc powder gives the polymeric Ti(III) derivative (cyclopentadienyl)titanium dichloride: : A related reduction can be effected with cobaltocene: : Other evidence for the Lewis acidity of the trichloride is the ready formation of adducts with phosphine ligands: : See also * (Cyclopentadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zirconium(IV) Compounds
Zirconium is a chemical element; it has symbol Zr and atomic number 40. First identified in 1789, isolated in impure form in 1824, and manufactured at scale by 1925, pure zirconium is a lustrous transition metal with a greyish-white color that closely resembles hafnium and, to a lesser extent, titanium. It is solid at room temperature, ductile, malleable and corrosion-resistant. The name ''zirconium'' is derived from the name of the mineral zircon, the most important source of zirconium. The word is related to Persian '' zargun'' (zircon; ''zar-gun'', "gold-like" or "as gold"). Besides zircon, zirconium occurs in over 140 other minerals, including baddeleyite and eudialyte; most zirconium is produced as a byproduct of minerals mined for titanium and tin. Zirconium forms a variety of inorganic compounds, such as zirconium dioxide, and organometallic compounds, such as zirconocene dichloride. Five isotopes occur naturally, four of which are stable. The metal and its alloys are main ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloro Complexes
Chlorine is a chemical element; it has symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Pauling scale, behind only oxygen and fluorine. Chlorine played an important role in the experiments conducted by medieval alchemists, which commonly involved the heating of chloride salts like ammonium chloride ( sal ammoniac) and sodium chloride ( common salt), producing various chemical substances containing chlorine such as hydrogen chloride, mercury(II) chloride (corrosive sublimate), and . However, the nature of free chlorine gas as a separate substance was only recognised around 1630 by Jan Baptist van Helmont. Car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organozirconium Compounds
Organozirconium chemistry is the science of exploring the properties, structure, and reactivity of organozirconium compounds, which are organometallic compounds containing chemical bonds between carbon and zirconium. Organozirconium compounds have been widely studied, in part because they are useful catalysts in Ziegler-Natta polymerization. Comparison with organotitanium chemistry Many organozirconium compounds have analogues on organotitanium chemistry. Zirconium(IV) is more resistant to reduction than titanium(IV) compounds, which often convert to Ti(III) derivatives. By the same token, Zr(II) is a particularly powerful reducing agent, forming robust dinitrogen complexes. Being a larger atom, zirconium forms complexes with higher Coordination number, coordination numbers, e.g. polymeric [CpZrCl3]n vs monomeric (Cyclopentadienyl)titanium trichloride, CpTiCl3 (Cp = C5H5). History Zirconocene dibromide was prepared in 1953 by a reaction of the cyclopentadienyl magnesium bromide an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadienyl Complexes
Cyclopentadienyl can refer to *Cyclopentadienyl anion Sodium cyclopentadienide is an organosodium compound with the formula C5H5Na. The compound is often abbreviated as NaCp, where Cp− is the cyclopentadienide anion. Sodium cyclopentadienide is a colorless solid, although samples often are pin ..., or cyclopentadienide, ** Cyclopentadienyl ligand * Cyclopentadienyl radical, • * Cyclopentadienyl cation, See also * Pentadienyl {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
