Organoiridium Complex

picture info	Organoiridium Complex Organoiridium chemistry is the chemistry of organometallic compounds containing an iridium-carbon chemical bond. Organoiridium compounds are relevant to many important processes including olefin hydrogenation and the industrial synthesis of acetic acid. They are also of great academic interest because of the diversity of the reactions and their relevance to the synthesis of fine chemicals. Classification based on principal oxidation states Organoiridium compounds share many characteristics with those of rhodium, but less so with cobalt. Iridium can exist in oxidation states of -III to +V, but iridium(I) and iridium(III) are the more common. iridium(I) compounds (d8 configuration) usually occur with square planar or trigonal bipyramidal geometries, whereas iridium(III) compounds (d6 configuration) typically have an octahedral geometry. Iridium(0) Iridium(0) complexes are binary carbonyls, the principal member being tetrairidium dodecacarbonyl, Ir4(CO)12. Unlike the related ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Chlorobis(cyclooctene)iridium Dimer Chlorobis(cyclooctene)iridium dimer is an organoiridium compound with the formula Ir2Cl2(C8H14)4, where C8H14 is ''cis''-cyclooctene. Sometimes abbreviated Ir2Cl2(coe)4, it is a yellow, air-sensitive solid that is used as a precursor to many other organoiridium compounds and catalysts. The compound is prepared by heating an alcohol solution of sodium hexachloroiridate with cyclooctene in ethanol. The coe ligands are easily displaced by other more basic ligand In coordination chemistry, a ligand is an ion or molecule ( functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's elec ...s, more so than the diene ligands in the related complex cyclooctadiene iridium chloride dimer. For example, with triphenylphosphine (PPh3), it reacts to give IrCl(PPh3)3: :Ir2Cl2(C8H14)4 + 6 PPh3 → 2 IrCl(PPh3)3 + 4 C8H14 References {{Iridium compounds Organoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Polyhedron (journal) ''Polyhedron'' is a peer-reviewed scientific journal covering the field of inorganic chemistry. It was established in 1955 as the ''Journal of Inorganic and Nuclear Chemistry'' and is published by Elsevier. Abstracting and indexing ''Polyhedron'' is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... of 3.052. References External links * {{Official Website, http://www.journals.elsevier.com/polyhedron/ Inorganic chemistry journals Elsevier academic journals Publications established in 1955 English-language journals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Pentamethylcyclopentadienyl Iridium Dichloride Dimer Pentamethylcyclopentadienyl iridium dichloride dimer is an organometallic compound with the formula C5(CH3)5IrCl2)sub>2, commonly abbreviated pIrCl2sub>2 This bright orange air-stable diamagnetic solid is a reagent in organometallic chemistry. Structure The compound has C2h symmetry. Each metal is pseudo-octahedral. The terminal and bridging Ir-Cl bonds have the lengths 2.39 and 2.45 Å, respectively. Preparation, reactions Pentamethylcyclopentadienyl iridium dichloride dimer was first prepared by the reaction of hydrated iridium trichloride with hexamethyl Dewar benzene. More conveniently, the compound is prepared by the reaction of hydrated iridium trichloride and pentamethylcyclopentadiene in hot methanol, from which the product precipitates :2 CpH + 2 IrCl3(H2O)3 → pIrCl2sub>2 + 2 HCl + 6 H2O The Ir-'' μ''-Cl bonds are labile and can be cleaved to give a variety of adducts of the general formula CpIrCl2L. Such adducts undergo further substitution to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Ammonium Hexachloroiridate Ammonium hexachloroiridate(IV) is the inorganic compound with the formula (NH4)2 rCl6 This dark brown solid is the ammonium salt of the iridium(IV) complex rCl6sup>2−. It is a commercially important iridium compound one of the most common complexes of iridium(IV). A related but ill-defined compound is iridium tetrachloride, which is often used interchangeably. Structure The compound has been characterized by X-ray crystallography. The salt crystallizes in a cubic motif like that of ammonium hexachloroplatinate. The rCl6sup>2− centers adopt octahedral molecular geometry. Uses It is a key intermediate in the isolation of iridium from ores. Most other metals form insoluble sulfides when aqueous solutions of their chlorides are treated with hydrogen sulfide, but rCl6sup>2− resists ligand substitution. Upon heating under hydrogen, the solid salt converts to the metal: : (NH4)2 rCl6 + 2 H2 → Ir + 6 HCl + 2 NH3 Bonding The electronic structure of ammonium he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Iridium Trichloride Iridium(III) chloride is the inorganic compound with the formula IrCl3. The anhydrous compound is relatively rare, but the related hydrate is useful for preparing other iridium compounds. The anhydrous salt is a dark green crystalline solid. More commonly encountered is the trihydrate IrCl3(H2O)3. Preparation Iridium is separated from the other platinum group metals as crystalline ammonium hexachloroiridate, (NH4)2 rCl6 which can be reduced to iridium metal in a stream of hydrogen. The spongy Ir thus produced reacts with chlorine at 300–400 °C to give iridium(III) chloride. Hydrated iridium trichloride is obtained by heating hydrated iridium(III) oxide with hydrochloric acid. Structure Like the related rhodium compound, IrCl3 adopts the structure seen for aluminium chloride. This is the monoclinic α polymorph. A rhombohedral β polymorph also exists. Both polymorphs have effectively the same anion lattice but differ in the octahedral interstices the iridium ions o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Rhodocene Rhodocene is a chemical compound with the formula . Each molecule contains an atom of rhodium bound between two planar aromatic systems of five carbon atoms known as cyclopentadienyl rings in a sandwich arrangement. It is an organometallic compound as it has ( haptic) covalent rhodium–carbon bonds. The radical is found above or when trapped by cooling to liquid nitrogen temperatures (). At room temperature, pairs of these radicals join via their cyclopentadienyl rings to form a dimer, a yellow solid. The history of organometallic chemistry includes the 19th-century discoveries of Zeise's salt and nickel tetracarbonyl. These compounds posed a challenge to chemists as the compounds did not fit with existing chemical bonding models. A further challenge arose with the discovery of ferrocene, the iron analogue of rhodocene and the first of the class of compounds now known as metallocenes. Ferrocene was found to be unusually chemically stable, as were analogous chemical struct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Journal Of Organometallic Chemistry The ''Journal of Organometallic Chemistry'' is a peer-reviewed scientific journal published by Elsevier, covering research on organometallic chemistry. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 2.345. References External links * Organic chemistry journals Elsevier academic journals Publications established in 1964 English-language journals Monthly journals {{chem-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Cyclopentadienyl Cyclopentadienyl can refer to Cyclopentadienyl anion, or cyclopentadienide, Cyclopentadienyl ligand Cyclopentadienyl radical, • Cyclopentadienyl cation, See also Pentadienyl In organic chemistry, pentadienyl refers to the organic radical, anion, or cation with the formula , where ''z'' = 0, −1, +1, respectively. Organometallic chemistry In organometallic chemistry, the pentadienyl anion is a ligand, the acyclic ana ... {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Crabtree's Catalyst Crabtree's catalyst is an organoiridium compound with the formula [1,5-Cyclooctadiene, C8H12IrTricyclohexylphosphine, P(C6H11)3pyridine, C5H5N]PF6. It is a homogeneous catalyst for hydrogenation and hydrogen-transfer reactions, developed by Robert H. Crabtree. This air stable orange solid is commercially available and known for its directed hydrogenation to give trans stereoselectivity with respective of directing group. Structure and synthesis The complex has a square planar molecular geometry, as expected for a d8 complex. It is prepared from cyclooctadiene iridium chloride dimer. Reactivity Crabtree’s catalyst is effective for the hydrogenations of mono-, di-, tri-, and tetra-substituted substrates. Whereas Wilkinson’s catalyst and the Schrock–Osborn catalyst do not catalyze the hydrogenation of a tetrasubstituted olefin, Crabtree’s catalyst does so to at high turnover frequencies (table). : The catalyst is reactive at room temperature. The reaction is robust without ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]