|
Compounds Of Palladium(III)
In chemistry, compounds of palladium(III) feature the noble metal palladium in the unusual +3 oxidation state (in most of its compounds, palladium has the oxidation state II). Compounds of Pd(III) occur in mononuclear and dinuclear forms. Palladium(III) is most often invoked, not observed in mechanistic organometallic chemistry. Mononuclear compounds Pd(III) has a d7 electronic configuration, which leads to a Jahn-Teller distorted octahedral geometry. The geometry could also be viewed as being intermediate between square-planar and octahedral. These complexes are low-spin and paramagnetic. The first Pd(III) complex characterized by X-ray crystallography was reported in 1987. It was obtained by oxidation of the 1,4,7-trithiacyclononane (ttcn) complex d(ttcn)2sup>3+. X-Ray crystallography revealed the expected Jahn-Teller distorted octahedral geometry, in spite of the highly symmetric structure of the ligand. The first organometallic Pd(III) complex characterized by X-Ray ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a Chemical reaction, reaction with other Chemical substance, substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both Basic research, basic and Applied science, applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant growth (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the properties ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrocyclic
Macrocycles are often described as molecules and ions containing a ring of twelve or more atoms. Classical examples include the crown ethers, calixarenes, porphyrins, and cyclodextrins. Macrocycles describe a large, mature area of chemistry. Synthesis The formation of macrocycles by ring-closure is called macrocylization. Pioneering work was reported for studies on terpenoid macrocycles. The central challenge to macrocyclization is that ring-closing reactions do not favor the formation of large rings. Instead, small rings or polymers tend to form. This kinetic problem can be addressed by using high-dilution reactions, whereby intramolecular processes are favored relative to polymerizations. Some macrocyclizations are favored using template reactions. Templates are ions, molecules, surfaces etc. that bind and pre-organize compounds, guiding them toward formation of a particular ring size. The crown ethers are often generated in the presence of an alkali metal cation, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-phenylpyridine
2-Phenylpyridine is an organic compound with the formula C6H5C5H4N (or C11H9N). It is a colourless viscous liquid. The compound and related derivatives have attracted interest as precursors to highly fluorescent metal complexes of possible value as organic light emitting diodes (OLEDs). The compound is prepared by the reaction of phenyl lithium with pyridine: :C6H5Li + C5H5N → C6H5-C5H4N + LiH The reaction of 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. ... with 2-phenylpyridine proceeds via cyclometallation to give the chloride-bridged complex: :4 C6H5-C5H4N + 2 IrCl3(H2O)3 → Ir2Cl2(C6H4-C5H4N)4 + 4 HCl This complex can be converted to the pictured tris(cyclometallated) derivative tris(2-phenylpyridine)iridium. References Further reading * {{DEF ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetoxylation
: In organic chemistry, acetylation is an organic esterification reaction with acetic acid. It introduces an acetyl group into a chemical compound. Such compounds are termed ''acetate esters'' or simply ''acetates''. Deacetylation is the opposite reaction, the removal of an acetyl group from a chemical compound. Organic synthesis Acetate esters and acetamides are generally prepared by acetylations. Acetylations are often used in making C-acetyl bonds in Friedel-Crafts reactions. Carbanions and their equivalents are susceptible to acetylations. Acetylation reagents Many acetylations are achieved using these three reagents: *Acetic anhydride. This reagent is common in the laboratory; its use cogenerates acetic acid. *Acetyl chloride. This reagent is also common in the laboratory, but its use cogenerates hydrogen chloride, which can be undesirable. *Ketene. At one time acetic anhydride was prepared by the reaction of ketene with acetic acid: :H2C=C=O + CH3COOH -> (CH3CO)2O\De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium(III)10
Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, dentistry, medicine, hydrogen purification, chemical applications, groundwater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallacycle
In organometallic chemistry, a metallacycle is a derivative of a carbocyclic compound wherein a metal has replaced at least one carbon center; this is to some extent similar to heterocycles. Metallacycles appear frequently as reactive intermediates in catalysis, e.g. olefin metathesis and alkyne trimerization. In organic synthesis, directed ortho metalation is widely used for the functionalization of arene rings via C-H activation. One main effect that metallic atom substitution on a cyclic carbon compound is distorting the geometry due to the large size of typical metals. Nomenclature Typically, metallacycles are cyclic compounds with two metal carbon bonds. Many compounds containing metals in rings are known, for example chelate rings. Usually, such compounds are not classified as metallacycles, but the naming conventions are not rigidly followed. Within the area of coordination chemistry and supramolecular chemistry, examples include metallacrowns, metallacryptands, metalla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium(III)9
Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, dentistry, medicine, hydrogen purification, chemical applications, groundwater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium(III)8
Palladium is a chemical element with the Symbol (chemistry), symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the 2 Pallas, asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas (daughter of Triton), Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its Congener (chemistry), congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium(III)7
Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, dentistry, medicine, hydrogen purification, chemical applications, groundw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triazabicyclodecene
Triazabicyclodecene (1,5,7-triazabicyclo .4.0ec-5-ene or TBD) is an organic compound consisting of a bicyclic guanidine. For a charge-neutral compound, it is a relatively strong base that is effectively for a variety of organic transformations. TBD is colorless solid that is soluble in a variety of solvents. Reactivity As a strong base, TBD fully deprotonates most phenols, carboxylic acids, and some C-acids. It catalyzes a variety of reactions including Michael reactions, Henry reactions (nitroaldol reactions), transesterification reactions, and Knoevenagel condensations. Deprotonation at the 7-position gives a particularly electron-rich ligand as manifested in the redox properties of ditungsten tetra(hpp). See also * 1,8-Diazabicyclo(5.4.0)undec-7-ene, a structurally related strong base * 7-Methyl-TBD 7-Methyl-1,5,7-triazabicyclo .4.0ec-5-ene (mTBD) is a bicyclic strong guanidine base (p''K''a = 25.43 in CH3CN and p''K''a = 17.9 in THF). mTBD, lik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium(III)6
Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, dentistry, medicine, hydrogen purification, chemical applications, groundw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
6.png "Click for more on -> Compounds Of Palladium(III)")
_Schematic.png "Click for more on -> 2-phenylpyridine")
2.jpg "Click for more on -> Palladium(III)10")
.png "Click for more on -> Metallacycle")