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Bis(triphenylphosphine)palladium(II) Chloride
Bis(triphenylphosphine)palladium chloride is a coordination compound of palladium containing two triphenylphosphine and two chloride ligands. It is a yellow solid that is soluble in some organic solvents. It is used for palladium-catalyzed coupling reactions, e.g. the Sonogashira–Hagihara reaction. The complex is Square planar molecular geometry, square planar. Many analogous complexes are known with different phosphine ligands. Preparation and reactions This compound may be prepared by treating palladium(II) chloride with triphenylphosphine: :PdCl2 + 2 PPh3 → PdCl2(PPh3)2 Upon reduction with hydrazine in the presence of excess triphenylphosphine, the complex is a precursor to tetrakis(triphenylphosphine)palladium, Pd(PPh3)4: :2 PdCl2(PPh3)2 + 4 PPh3 + 5 N2H4 → 2 Pd(PPh3)4 + N2 + 4 N2H5+Cl− Structure Several crystal structures containing PdCl2(PPh3)2 have been reported. In all of the structures, PdCl2(PPh3)2 adopts a Square planar molecular geometry, square ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis(triphenylphosphine)platinum Chloride
Bis(triphenylphosphine)platinum chloride is a metal phosphine complex with the formula PtCl2 (C6H5)3sub>2. Cis- and trans isomers are known. The cis isomer is a white crystalline powder, while the trans isomer is yellow. Both isomers are square planar about the central platinum atom. The cis isomer is used primarily as a reagent for the synthesis of other platinum compounds. Preparation The cis isomer is the prepared by heating solutions of platinum(II) chlorides with triphenylphosphine. For example, starting from potassium tetrachloroplatinate: :K2PtCl4 + 2 PPh3 → ''cis''-Pt(PPh3)2Cl2 + 2 KCl The trans isomer is the prepared by treating potassium trichloro(ethylene)platinate(II) (Zeise's salt) with triphenylphosphine: :KPt(C2H4)Cl3 + 2 PPh3 → ''trans''-Pt(PPh3)2Cl2 + KCl + C2H4 With heating or in the presence of excess PPh3, the trans isomer converts to the cis complex. The latter complex is the thermodynamic product due to triphenylphosphine being a strong trans effect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylphosphine Complexes
Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to P Ph3 or Ph3P. It is widely used in the synthesis of organic and organometallic compounds. PPh3 exists as relatively air stable, colorless crystals at room temperature. It dissolves in non-polar organic solvents such as benzene and diethyl ether. Preparation and structure Triphenylphosphine can be prepared in the laboratory by treatment of phosphorus trichloride with phenylmagnesium bromide or phenyllithium. The industrial synthesis involves the reaction between phosphorus trichloride, chlorobenzene, and sodium: :PCl3 + 3 PhCl + 6 Na → PPh3 + 6 NaCl Triphenylphosphine crystallizes in triclinic and monoclinic modification. In both cases, the molecule adopts a pyramidal structure with propeller-like arrangement of the three phenyl groups. Principal reactions with chalcogens, halogens, and acids Oxidation Triphenylphosphine undergoes slow o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium Compounds
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] |
Dichlorobis(triphenylphosphine)nickel(II)
Dichlorobis(triphenylphosphine)nickel(II) refers to a pair of metal phosphine complexes with the formula NiCl2 (C6H5)3sub>2. The compound exists as two isomers, a paramagnetic dark blue solid and a diamagnetic red solid. These complexes function as catalysts for organic synthesis.Montgomery, J. Science of Synthesis Georg Thiene Verlag KG, Vol. 1, p 11, CODEN: SSCYJ9 Synthesis and structure The blue isomer is prepared by treating hydrated nickel chloride with triphenylphosphine in alcohols or glacial acetic acid: :NiCl2•6H2O + 2 PPh3 → NiCl2(PPh3)2 + 6 H2O When allowed to crystallise from chlorinated solvents, the tetrahedral isomer converts to the square planar isomer. The square planar form is red and diamagnetic. The phosphine ligands are trans with respective Ni-P and Ni-Cl distances of 2.24 and 2.17 Å. The blue form is paramagnetic and features tetrahedral Ni(II) centers. In this isomer, the Ni-P and Ni-Cl distances are elongated at 2.32 and 2.21 Å. As illustrated by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis(triphenylphosphine)platinum(II) Chloride
Bis(triphenylphosphine)platinum chloride is a metal phosphine complex with the formula PtCl2 (C6H5)3sub>2. Cis- and trans isomers are known. The cis isomer is a white crystalline powder, while the trans isomer is yellow. Both isomers are square planar about the central platinum atom. The cis isomer is used primarily as a reagent for the synthesis of other platinum compounds. Preparation The cis isomer is the prepared by heating solutions of platinum(II) chlorides with triphenylphosphine. For example, starting from potassium tetrachloroplatinate: :K2PtCl4 + 2 PPh3 → ''cis''-Pt(PPh3)2Cl2 + 2 KCl The trans isomer is the prepared by treating potassium trichloro(ethylene)platinate(II) (Zeise's salt) with triphenylphosphine: :KPt(C2H4)Cl3 + 2 PPh3 → ''trans''-Pt(PPh3)2Cl2 + KCl + C2H4 With heating or in the presence of excess PPh3, the trans isomer converts to the cis complex. The latter complex is the thermodynamic product due to triphenylphosphine being a strong trans effect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonogashira Coupling
The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon–carbon bonds. It employs a palladium catalyst as well as copper co-catalyst to form a carbon–carbon bond between a terminal alkyne and an aryl or vinyl halide. :* : aryl or vinyl :* : arbitrary :* X: I, Br, Cl or OTf The Sonogashira cross-coupling reaction has been employed in a wide variety of areas, due to its usefulness in the formation of carbon–carbon bonds. The reaction can be carried out under mild conditions, such as at room temperature, in aqueous media, and with a mild base, which has allowed for the use of the Sonogashira cross-coupling reaction in the synthesis of complex molecules. Its applications include pharmaceuticals, natural products, organic materials, and nanomaterials. Specific examples include its use in the synthesis of tazarotene, which is a treatment for psoriasis and acne, and in the preparation of SIB-1508Y, also known as Altinicline, a nicotinic recep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boronic Acid
A boronic acid is an organic compound related to boric acid () in which one of the three hydroxyl groups () is replaced by an alkyl or aryl group (represented by R in the general formula ). As a compound containing a carbon–boron bond, members of this class thus belong to the larger class of organoboranes. Boronic acids act as Lewis acids. Their unique feature is that they are capable of forming reversible covalent complexes with sugars, amino acids, hydroxamic acids, etc. (molecules with vicinal, (1,2) or occasionally (1,3) substituted Lewis base donors (alcohol, amine, carboxylate)). The p''K''a of a boronic acid is ~9, but they can form tetrahedral boronate complexes with p''K''a ~7. They are occasionally used in the area of molecular recognition to bind to saccharides for fluorescent detection or selective transport of saccharides across membranes. Boronic acids are used extensively in organic chemistry as chemical building blocks and intermediates predominantly in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suzuki Reaction
The Suzuki reaction is an organic reaction, classified as a cross-coupling reaction, where the coupling partners are a boronic acid and an organohalide and the catalyst is a palladium(0) complex. It was first published in 1979 by Akira Suzuki, and he shared the 2010 Nobel Prize in Chemistry with Richard F. Heck and Ei-ichi Negishi for their contribution to the discovery and development of palladium-catalyzed cross-couplings in organic synthesis. This reaction is also known as the Suzuki–Miyaura reaction or simply as the Suzuki coupling. It is widely used to synthesize poly olefins, styrenes, and substituted biphenyls. Several reviews have been published describing advancements and the development of the Suzuki reaction. The general scheme for the Suzuki reaction is shown below, where a carbon-carbon single bond is formed by coupling a halide (R1-X) with an organoboron species (R2-BY2) using a palladium catalyst and a base. Reaction mechanism The mechanism of the Suzuki r ... [...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] |
Acta Crystallographica Section E
''Acta Crystallographica'' is a series of peer-reviewed scientific journals, with articles centred on crystallography, published by the International Union of Crystallography (IUCr). Originally established in 1948 as a single journal called ''Acta Crystallographica'', there are now six independent ''Acta Crystallographica'' titles: *'' Acta Crystallographica Section A: Foundations and Advances'' *'' Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials'' *'' Acta Crystallographica Section C: Structural Chemistry'' *'' Acta Crystallographica Section D: Structural Biology'' *'' Acta Crystallographica Section E: Crystallographic Communications'' *'' Acta Crystallographica Section F: Structural Biology Communications'' ''Acta Crystallographica'' has been noted for the high quality of the papers that it produces, as well as the large impact that its papers have had on the field of crystallography. The current six journals form part of the journal port ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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